i need to ask so im trying to do this calculation and it gives me two answers why and how?
+118609 \((3x+3)(x-4)=3(x+1)\\ 3x^2-12x+3x-12=3x+3\\ 3x^2-9x-12=3x+3\\ 3x^2-9x-12-3x-3=3x+3-3x-3\\ 3x^2-12x-15=0\\ \text{divide both sides by 3}\\ x^2-4x-5=0\\ (x-5)(x+1)=0\)
now if 2 things multiply together to give 0 then one of them, or both of them, must equal 0.
so
x-5=0 or x+1=0
x=5 or x=-1
