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Question from jordan, a student:

8(y + 3) + 9(y + 2) = y - 3

Hi Jordan,

I am going to solve a similar problem,

Solve for x if 5(x + 2) + 2(x - 3) = 3(x + 4)

First you need to expand each of the three terms in this equation keeping in mind that in each case everything inside the parentheses is multiplied by the number in front. For example

5(x + 2) = 5 × x + 5 × 2 = 5x + 10

Hence expanding all three terms I get

5x + 10 + 2x - 6 = 3x + 12

Now collect like terms on the left side. 5x plus 2x is 7x and 10 minus 6 is 4 so the equation becomes

7x + 4 = 3x + 12

I want all the "x-terms" on the left of the equality so subtract 3x from both sides to get

7x + 4 - 3x = 3x + 12 - 3x or
4x + 4 = 12

Now subtract 4 from both sides to obtain

4x + 4 - 4 = 12 - 4 or
4x = 8.

Thus x = 2.

Now try your problem,
Penny

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