Last question guys :) I will give a medal.

Eduardo solved the following inequality and his work is shown below:

−5(x + 4) + 21 ≥ −3 + 4(x − 8)
−5x − 20 + 21 ≥ −3 + 4x − 32
−5x + 1 ≥ 4x − 35
−9x ≥ −36
x ≥ 4

What mistake did Eduardo make in solving the inequality?

Question

Last question guys :) I will give a medal.





Eduardo solved the following inequality and his work is shown below:

−5(x + 4) + 21 ≥ −3 + 4(x − 8)
−5x − 20 + 21 ≥ −3 + 4x − 32
−5x + 1 ≥ 4x − 35
−9x ≥ −36
x ≥ 4

What mistake did Eduardo make in solving the inequality?

anonymous · Answer

forgot to flip the inequality when dividing by $-4$

stormswan · Answer

oh. lol I was just about to ask if that was the mistake, but you beat me to it! thanks :P