Question

Carlos 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

a)He should have substituted 5 + 2x

b)He did not distribute correctly

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

d)He made no mistake

Answer 1

Take a look here:
x − 2(5 − 2x) = 10
x + 10 + 4x = 10
the mistake is in there somewhere. Tell me what you think.

Answer 2

idk?

Answer 3

Here's an example.
- 5(4 + x) --> -20 - 5x
See how the negative was distributed? This is called the distributive property. Now what do you think it is?

Answer 4

he did not distribute correctly?

Answer 5

Yeah

Answer 6

thanks

Answer 7

np :)