Let's solve your equation step-by-step.
81=2x+7x
Step 1: Simplify both sides of the equation.
81=2x+7x
81=(2x+7x)(Combine Like Terms)
81=9x
81=9x
Step 2: Flip the equation.
9x=81
Step 3: Divide both sides by 9.
[tex] \dfrac{9x}{9} = \dfrac{81}{9} \\ x = 9[/tex]
