Let's solve your equation step-by-step.
3x+6=x9
Step 1: Cross-multiply.
3x+6=x9
(3)*(9)=x*(x+6)
27=x2+6x
Step 2: Subtract x^2+6x from both sides.
27−(x2+6x)=x2+6x−(x2+6x)
−x2−6x+27=0
Step 3: Factor left side of equation.
(−x+3)(x+9)=0
Step 4: Set factors equal to 0.
−x+3=0 or x+9=0
x=3 or x=−9