Answer: x=7
Step-by-step explanation:
plug y into equation...
x-(-4x+23)=12
solve...
x+-1(-4x+23)=12
x+-1(-4x)+-1(23)=12
x+4x-23=12
5x-23=12
5x=35
x=7
Answer:
A=2(wl+hl+hw)