Question

if ∠1 is 70°, then ∠7 is how many degrees? 70 110 80 100

Explanation:

Step1: Identify angle - relationship

$\angle1$ and $\angle7$ are exterior - alternate angles when two parallel lines are cut by a transversal.

Step2: Apply angle - property

Exterior - alternate angles are equal. So $\angle7=\angle1$.

Answer:

70