How do you simplify #(4y-9)-(3y+10)#?
A place where students commonly make mistakes with is the terms after the subtraction sign, in this case
Pretend that there is a negative 1 in front of
Distribute that negative one to the terms in the parenthesis, to get
Combine that with the remaining expression and then simplify.
Combine like terms:
Put those together to get the answer of: