Question

Becky and tommy are asked to solve -4x-25=8x+15 identity where one of them made an error

Answer 1

I feel sorry for Becky and Tommy. The one who didn't come up with x=-10/3 made an error.

first bring 8x to the left and -25 to the right and simplify:

-4x-8x = 25+15 => -12x = 40

x = -40/12 = -10/3

Answer 2

Procedure to solve the equation in one variable

-4 x-25= 8 x+15

Taking variable on one side and constant on another side of equation

- 4 x - 8 x = 15 + 25(When one quantity goes on other side of equation , the sign preceding it changes)

- 12 x= 40

x = $\frac{40}{-12}=\frac{-10}{3}$

By looking at the solution described above , you can find yourself who has done the mistake between Becky and Tommy and  can also identify the error and rectify it.