Answer:
m∠4 = m∠1 + m∠3
Step-by-step explanation:
The measure of an exterior angle of a triangle is equal to the sum of its two opposite interior angles
Now, examining the given triangle, we can note that:
∠4 is an exterior angle
∠1 and ∠3 are its two opposite interior angles
Based on the givens and the above theorem, we can conclude that:
m∠4 = m∠1 + m∠3
Hope this helps :)
