Question

Which step he made an error and what he supposed to do instead?

Answer 1

step 1

Explanation:

`for \: the \: first \: part \: of \: step \: one \: 9 {y}^(2) - 4y - 6 \: is \: correct`

however the second part of the equation is incorrectly expanded.

-(3y^2 + 6y + 2)

above states (-3y^2 add 6y add 2)

the -3y^2 is correct because a negative variable and positive variable make a negative variable

however; it should be (-3y^2 minus 6y minus 2 instead of add) because when two variables of different signs (negative and positive) are multiplied the resultant should be negative.