Plane Geometry - ACT Math

Card 0 of 20

Question

Hexex11

All of the angles marked are exterior angles.

What is the value of in degrees? Round to the nearest hundredth.

Answer

There are two key things for a question like this. The first is to know that a polygon has a total degree measure of:

, where is the number of sides.

Therefore, a hexagon like this one has:

.

Next, you should remember that all of the exterior angles listed are supplementary to their correlative interior angles. This lets you draw the following figure:

Hexex12

Now, you just have to manage your algebra well. You must sum up all of the interior angles and set them equal to . Since there are angles, you know that the numeric portion will be or . Thus, you can write:

Simplify and solve for :

This is or .

Compare your answer with the correct one above

Question

The sum of all the angles inside of a regular hexagon is . Determine the value of one angle.

Answer

In a regular hexagon, all of the sides are the same length, and all of the angles are equivalent. The problem tells us that all of the angles inside the hexagon sum to . To find the value of one angle, we must divide by , since there are angles inside of a hexagon.

Compare your answer with the correct one above

Question

Hexex21

The figure above is a hexagon. All of the angles listed (except the interior one) are exterior angles to the hexagon's interior angles.

What is the value of ?

Answer

There are two key things for a question like this. The first is to know that a polygon has a total degree measure of:

, where is the number of sides.

Therefore, a hexagon like this one has:

.

Next, you should remember that all of the exterior angles listed are supplementary to their correlative interior angles. This lets you draw the following figure:

Hexex22

Now, you just have to manage your algebra well. You must sum up all of the interior angles and set them equal to . Thus, you can write:

Solve for :

Compare your answer with the correct one above

Question

Q7

If the diagonals of the quadrilateral above were drawn in the figure, they would form four 90 degree angles at the center. In degrees, what is the value of ?

Answer

A quadrilateral is considered a kite when one of the following is true:

(1) it has two disjoint pairs of sides are equal in length or

(2) one diagonal is the perpendicular bisector of the other diagonal. Given the information in the question, we know (2) is definitely true.

To find we must first find the values of all of the angles.

The sum of angles within any quadrilateral is 360 degrees.

Therefore .

To find :

Compare your answer with the correct one above

Question

A kite has one set of opposite interior angles where the two angles measure and , respectively. Find the measurement for one of the two remaining interior angles in this kite.

Answer

The sum of the interior angles of any polygon can be found by applying the formula:

degrees, where is the number of sides in the polygon.

By definition, a kite is a polygon with four total sides (quadrilateral). The sum of the interior angles of any quadrilateral must equal: degrees degrees degrees. Additionally, kites must have two sets of equivalent adjacent sides & one set of congruent opposite angles.

The missing angle can be found by finding the sum of the non-congruent opposite angles. Then divide the difference between degrees and the non-congruent opposite angles sum by :

This means that is the sum of the remaining two angles, which must be opposite congruent angles. Therefore, the measurement for one of the angles is:

Compare your answer with the correct one above

Question

Kite vt act

Using the kite shown above, find the sum of the two remaining congruent interior angles.

Answer

The sum of the interior angles of any polygon can be found by applying the formula:

degrees, where is the number of sides in the polygon.

By definition, a kite is a polygon with four total sides (quadrilateral). The sum of the interior angles of any quadrilateral must equal: degrees degrees degrees. Additionally, kites must have two sets of equivalent adjacent sides & one set of congruent opposite angles.

To find the sum of the remaining two angles, determine the difference between degrees and the sum of the non-congruent opposite angles.

The solution is:

degrees

Thus, degrees is the sum of the remaining two opposite angles.

Check:

Compare your answer with the correct one above

Question

A kite has one set of opposite interior angles where the two angles measure and , respectively. Find the measurement for one of the two remaining interior angles in this kite.

Answer

The sum of the interior angles of any polygon can be found by applying the formula:

degrees, where is the number of sides in the polygon.

A kite is a polygon with four total sides (quadrilateral). The sum of the interior angles of any quadrilateral must equal: degrees degrees degrees. Additionally, kites must have two sets of equivalent adjacent sides & one set of congruent opposite angles.

The missing angle can be found by finding the sum of the non-congruent opposite angles. Then divide the difference between degrees and the non-congruent opposite angles sum by :

This means that is the sum of the remaining two angles, which must be opposite congruent angles. Therefore, the measurement for one of the angles is:

Compare your answer with the correct one above

Question

Kite vt act

Using the kite shown above, find the sum of the two remaining congruent interior angles.

Answer

The sum of the interior angles of any polygon can be found by applying the formula:

degrees, where is the number of sides in the polygon.

A kite is a polygon with four total sides (quadrilateral). The sum of the interior angles of any quadrilateral must equal: degrees degrees degrees. Additionally, kites must have two sets of equivalent adjacent sides & one set of congruent opposite angles.

To find the sum of the remaining two angles, determine the difference between degrees and the sum of the non-congruent opposite angles.

The solution is:

degrees

Thus, degrees is the sum of the remaining two opposite angles.

Compare your answer with the correct one above

Question

A kite has one set of opposite interior angles where the two angles measure and , respectively. Find the measurement for one of the two remaining interior angles in this kite.

Answer

The sum of the interior angles of any polygon can be found by applying the formula:

degrees, where is the number of sides in the polygon.

By definition, a kite is a polygon with four total sides (quadrilateral). The sum of the interior angles of any quadrilateral must equal: degrees degrees degrees. Additionally, kites must have two sets of equivalent adjacent sides & one set of congruent opposite angles.

The missing angle can be found by finding the sum of the non-congruent opposite angles. Then divide the difference between degrees and the non-congruent opposite angles sum by :

This means that is the sum of the remaining two angles, which must be opposite congruent angles. Therefore, the measurement for one of the angles is:

Compare your answer with the correct one above

Question

A kite has one set of opposite interior angles where the two angles measure and , respectively. Find the measurement of the sum of the two remaining interior angles in this kite.

Answer

The sum of the interior angles of any polygon can be found by applying the formula:

degrees, where is the number of sides in the polygon.

By definition, a kite is a polygon with four total sides (quadrilateral). The sum of the interior angles of any quadrilateral must equal: degrees degrees degrees. Additionally, kites must have two sets of equivalent adjacent sides & one set of congruent opposite angles.

To find the sum of the remaining two angles, determine the difference between degrees and the sum of the non-congruent opposite angles.

The solution is:

degrees

This means that degrees is the sum of the remaining two opposite angles and that each have an individual measurement of degrees.

Check:

Compare your answer with the correct one above

Question

A kite has one set of opposite interior angles where the two angles measure and , respectively. Find the measurement for one of the two remaining interior angles in this kite.

Answer

The sum of the interior angles of any polygon can be found by applying the formula:

degrees, where is the number of sides in the polygon.

A kite is a polygon with four total sides (quadrilateral). The sum of the interior angles of any quadrilateral must equal: degrees degrees degrees. Additionally, kites must have two sets of equivalent adjacent sides & one set of congruent opposite angles.

The missing angle can be found by finding the sum of the non-congruent opposite angles. Then divide the difference between degrees and the non-congruent opposite angles sum by :

This means that is the sum of the remaining two angles, which must be opposite congruent angles. Therefore, the measurement for one of the angles is:

Compare your answer with the correct one above

Question

A kite has one set of opposite interior angles where the two angles measure and , respectively. Find the measurement of the sum of the two remaining interior angles.

Answer

The sum of the interior angles of any polygon can be found by applying the formula:

degrees, where is the number of sides in the polygon.

By definition, a kite is a polygon with four total sides (quadrilateral). The sum of the interior angles of any quadrilateral must equal: degrees degrees degrees. Additionally, kites must have two sets of equivalent adjacent sides & one set of congruent opposite angles.

To find the sum of the remaining two angles, determine the difference between degrees and the sum of the non-congruent opposite angles.

The solution is:

degrees

This means that degrees is the sum of the remaining two opposite angles.

Check:

Compare your answer with the correct one above

Question

A kite has one set of opposite interior angles where the two angles measure and , respectively. Find the measurement for one of the two remaining interior angles in this kite.

Answer

The sum of the interior angles of any polygon can be found by applying the formula:

degrees, where is the number of sides in the polygon.

By definition, a kite is a polygon with four total sides (quadrilateral). The sum of the interior angles of any quadrilateral must equal: degrees degrees degrees. Additionally, kites must have two sets of equivalent adjacent sides & one set of congruent opposite angles.

The missing angle can be found by finding the sum of the non-congruent opposite angles. Then divide the difference between degrees and the non-congruent opposite angles sum by :

This means that is the sum of the remaining two angles, which must be opposite congruent angles. Therefore, the measurement for one of the angles is:

Compare your answer with the correct one above

Question

Kite vt act

Using the kite shown above, find the sum of the two remaining congruent interior angles.

Answer

The sum of the interior angles of any polygon can be found by applying the formula:

degrees, where is the number of sides in the polygon.

A kite is a polygon with four total sides (quadrilateral). The sum of the interior angles of any quadrilateral must equal: degrees degrees degrees. Additionally, kites must have two sets of equivalent adjacent sides & one set of congruent opposite angles.

To find the sum of the remaining two angles, determine the difference between degrees and the sum of the non-congruent opposite angles.

The solution is:

degrees

degrees

Thus, degrees is the sum of the remaining two opposite angles.

Compare your answer with the correct one above

Question

A kite has one set of opposite interior angles where the two angles measure and , respectively. Find the measurement for one of the two remaining interior angles in this kite.

Answer

The sum of the interior angles of any polygon can be found by applying the formula:

degrees, where is the number of sides in the polygon.

By definition, a kite is a polygon with four total sides (quadrilateral). The sum of the interior angles of any quadrilateral must equal: degrees degrees degrees. Additionally, kites must have two sets of equivalent adjacent sides & one set of congruent opposite angles.

The missing angle can be found by finding the sum of the non-congruent opposite angles. Then divide the difference between degrees and the non-congruent opposite angles sum by :

This means that is the sum of the remaining two angles, which must be opposite congruent angles. Therefore, the measurement for one of the angles is:

Compare your answer with the correct one above

Question

A kite has one set of opposite interior angles where the two angles measure and , respectively. Find the measurement of the sum of the two remaining interior angles.

Answer

The sum of the interior angles of any polygon can be found by applying the formula:

degrees, where is the number of sides in the polygon.

By definition, a kite is a polygon with four total sides (quadrilateral). The sum of the interior angles of any quadrilateral must equal: degrees degrees degrees. Additionally, kites must have two sets of equivalent adjacent sides & one set of congruent opposite angles.

To find the sum of the remaining two angles, determine the difference between degrees and the sum of the non-congruent opposite angles.

The solution is:

This means that is the sum of the remaining two opposite angles.

Compare your answer with the correct one above

Question

In a particular kite, one angle that lies between congruent sides measures , and one angle that lies between non-congruent sides measures . What is the measure of the angle opposite the angle?

Answer

One of the rules governing kites is that the angles which lie between non-congruent sides are congruent to each other. Thus, we know one of the missing angles is also . Since all angles in a quadrilateral must sum to , we know that the other missing angle is

Compare your answer with the correct one above

Question

In the parallellogram, what is the value of ?

Screen_shot_2013-07-15_at_9.42.14_pm

Answer

Opposite angles are equal, and adjacent angles must sum to 180.

Therefore, we can set up an equation to solve for z:

(z – 15) + 2z = 180

3z - 15 = 180

3z = 195

z = 65

Now solve for x:

2_z_ = x = 130°

Compare your answer with the correct one above

Question

Parallelogram_2

In parallelogram , . What is

Answer

In the above parallelogram, and are consecutive angles (i.e. next to each other). In a parallelogram, consecutive angles are supplementary, meaning they add to .

Compare your answer with the correct one above

Question

Parallelogram_2

In parallelogram , . What is ?

Answer

In parallelogram , and are opposite angles. In a parallelogram, opposite angles are congruent. This means these two angles are equal.

Compare your answer with the correct one above

Tap the card to reveal the answer