Question

solve for x.
(7x + 18)°
81°
x =

Explanation:

Step1: Identify vertical - angle relationship

Vertical angles are equal. $\angle DHI$ and the angle with measure $81^{\circ}$ are vertical angles. So $7x + 18=81$.

Step2: Solve the equation for x

Subtract 18 from both sides: $7x=81 - 18$. So $7x = 63$.

Step3: Isolate x

Divide both sides by 7: $x=\frac{63}{7}$.

Answer:

$9$