Question

if m<1 = 130 degrees, then m<8 = 50 90 none of the above 130

Explanation:

Step1: Identify angle - relationship

$\angle1$ and $\angle3$ are vertical angles, so $m\angle3=m\angle1 = 130^{\circ}$.

Step2: Use corresponding - angles property

$\angle3$ and $\angle7$ are corresponding angles for parallel lines $a$ and $m$ cut by transversal $t$, so $m\angle7=m\angle3 = 130^{\circ}$.

Step3: Find $m\angle8$

$\angle7$ and $\angle8$ are supplementary angles (linear - pair), so $m\angle7 + m\angle8=180^{\circ}$. Then $m\angle8=180 - m\angle7$. Substituting $m\angle7 = 130^{\circ}$, we get $m\angle8=180 - 130=50^{\circ}$.

Answer:

50