Trevor solved the system of equations below. What mistake did he make in his work?

2x + y = 5
x − 2y = 10

y = 5 − 2x
x − 2(5 − 2x) = 10
x − 10 + 4x = 10
5x − 10 = 10
5x = 0
x = 0

2(0) + y = 5
y = 5

He should have substituted 5 + 2x

He combined like terms incorrectly, it should have been 4x instead of 5x

He subtracted 10 from the right side instead of adding 10 to the right side

He made no mistake

Question

Trevor solved the system of equations below. What mistake did he make in his work?

2x + y = 5
x − 2y = 10

y = 5 − 2x
x − 2(5 − 2x) = 10
x − 10 + 4x = 10
5x − 10 = 10
5x = 0
x = 0

2(0) + y = 5
y = 5

 He should have substituted 5 + 2x

 He combined like terms incorrectly, it should have been 4x instead of 5x

 He subtracted 10 from the right side instead of adding 10 to the right side

 He made no mistake

jim_thompson5910 · Answer

are you able to see where he made the mistake?

anonymous · Answer

ummm  no thats  y i asked the question

jim_thompson5910 · Answer

Hint:

look at the lines

5x − 10 = 10
5x = 0

anonymous · Answer

probably dividing o into 5

jim_thompson5910 · Answer

there's a mistake when going from 5x − 10 = 10 to 5x = 0

anonymous · Answer

ohhhhhhh he subtracted 10 instead of adding

jim_thompson5910 · Answer

yep

anonymous · Answer

thanks

jim_thompson5910 · Answer

yw