Question

find m∠1. m∠1 = (type an integer or a fraction. do not include the degree symbol in your answer.)

Explanation:

Step1: Use vertical - angle property

Vertical angles are equal. So, $3x + 6=123$.

Step2: Solve for $x$

Subtract 6 from both sides: $3x=123 - 6=117$. Then divide both sides by 3: $x=\frac{117}{3}=39$.

Step3: Find $m\angle1$

$\angle1$ and the angle $(3x + 6)^{\circ}$ are vertical angles. Since $3x+6 = 123$, then $m\angle1 = 123$.

Answer:

123