How to subtract variables - ISEE Middle Level Quantitative Reasoning

It is easiest to begin by moving like terms together. Hence:

becomes

(Notice that is its own term.)

Now, consider the coefficients for each term.

For , you have

For , you have

Hence, the expression simplifies to:

This can be moved around to get the correct answer (which means the same thing):

Begin by distributing the two groups. Notice that you must distribute the subtraction through the groups:

becomes

Next, you should move like terms next to each other:

(Notice that is its own term.)

Now, combine terms.

For , you get

For , you get

Therefore, the final form of the expression is:

Begin by distributing. Thus,

becomes

(Don't forget that you have to distribute your subtraction for the second group.)

Combine like terms on the right side of the equation:

Next, move the values to the left side of the equation and all of the other values to the right side:

Combine like terms on the left:

Finally, divide everything by :

This comes out to be:

or

Begin by distributing the multiplied groups:

Next, move all similar factors together:

Now, combine each set of similar factors:

Therefore, our answer is:

This problem is not too difficult. Begin by moving all common terms next to each other:

Next, simplify each group of terms that has the same set of variables:

And do not forget that you are left with as well!

Now, combine all of these:

Begin by moving common factors next to each other. Thus,

becomes

Now, combine each set:

Remember, there still is also.

Therefore, the simplified form of the expression is:

also, since , it follows that

, and by the inequality properties,

making 9 the greater quantity.