Question

Please Help, I will give Brainliest!!!

Part A: If m1 = 53, what is m3?

Part B: Derrick states that DEF is an isosceles triangle. Is Derrick correct? Explain.

Answer 1

Part A: m3 would be 143 degrees by the exterior angle theorem.
Part B: Derrick is incorrect. The base angles would have to be the same by the Converse of the Base Angles Theorem. The angles would have to both be 45 degrees.

Answer 2

Answer:

A . 143 degrees

B.  Not isosceles.

Step-by-step explanation:

A.

m < 3 = 90 + m < 1    (by the external angle of triangle theorem)

= 90 + 53

= 143

B. If DEF is an isosceles m < 1 = m <2

and m < 2 = (180 -  143)            (adjacent angles are supplementary).

= 37 degrees but m<1 = 53 degrees so it is not isosceles.