Please show steps
If 3x + 7 = 10, what is -2x - 8?

-10

Step-by-step explanation:

first you need to solve the first equation

3x + 7 = 10

subtract 7 from both sides

3x + 7 - 7 = 10 - 7

3x = 3

divide both sides by 3

3x/3 = 3/3

x = 1

now substitute x in the second equation.

-2x - 8

-2(1) - 8

-2 - 8

-10

- 10

Step-by-step explanation:

Given

3x + 7 = 10 ( subtract 7 from both sides )

3x = 3 ( divide both sides by 3 )

x = 1

Thus

- 2x - 8 = - 2(1) - 8 = - 2 - 8 = - 10