Question

Given m∠D = 70°, m∠E = 42, and m∠EHG = 68°, prove DF is parallel to GH.

Answer 1

we know that

If DF is parallel to GH

then

the measure of the angle EGH must be equal to 70° by corresponding angles

so

Find the measure of the angle EGH

In the triangle EGH

the sum of the internal angles must be equal to 180 degrees

42°+68°+∠EGH=180°

solve for ∠EGH

∠EGH=180-(42+68)

∠EGH=180-110

∠EGH=70°

therefore

The lines DF and GH are parallel