Question

Solve the equation in two different ways. Choose one method of solving in detail 5x+7(x+1) = 5x - 21

Answer 1

METHOD 1:

5x+7(x+1)=5x-21

5x+7x+7=5x-21

12x+7=5x-21

12x-5x=-21-7

7x=-28

x=28/7

x=4

METHOD 2:

5x+7(x+1)=5x-21

5x+7(x+1)=5x-21-5x

7(x+1)=-21

7x+7=-21

7x=-28

x=4

Explanation:

METHOD 1:

5x+7(x+1)=5x-21

5x+7x+7=5x-21

12x+7=5x-21

12x-5x=-21-7

7x=-28

x=28/7

x=4

METHOD 2:

5x+7(x+1)=5x-21

5x+7(x+1)=5x-21-5x

7(x+1)=-21

7x+7=-21

7x=-28

x=4