Answer:
Step-by-step explanation:
(3x + 4)(x + 3)
3x^2 + 9x + 4x + 12
3x^2 + 13x + 12
I don't know how to explain
x=8
2x+9=3x+1
-3 -3
-9 -9
-1x=-8
divide both side by -1.
y=3x-7 that's the answer