Answer :

Answer:

m∠4 = 54°

m∠1 = 126°

Step-by-step explanation:

m∠6 ≅ 54° → given

∠6 ≅ ∠8 → vertical angles are congruent

∠8 ≅ ∠4 → corresponding angles are congruent

∠6 ≅∠4 → transitive property

m∠6 = m∠4 → definition of congruence (if they are congruent, their measures are equal)

m∠4 = 54° → transitive property

∠4 and ∠1 are linear pairs → given

∠4 and ∠1 are supplementary → definition of linear pairs

m∠4 + m∠1 = 180 → definition of supplementary angles

m∠1 = 126° → subtraction

I realize this is not the most efficient way to go about it, but it works!

My way of proving can be a little weird, so feel free to ask for clarification!