Answer:
Step-by-step explanation:
Angle sum property of triangle: Sum of all the angles of a triangle is 180
Alternate interior angles: When two parallel lines are intersected by a transversal, the pair of angles on the inner side of each of these lines but on the opposite side of the transversal are called alternate interior angles
In ΔABC,
∠1 + 90 + 38 = 180 {angle sum property of triangle}
∠1 + 128 = 180
∠1 = 180 - 128
AB // CD and AC is transversal.
{Alternate interior angles are equal}
In ΔACD,
∠2 + ∠3 + 63 = 180 {angle sum property of triangle}
∠2 + 38 +63 = 180
∠2 + 101 =180
∠2 = 180 - 101
The question said that it told you the base angles. A roof would have two equal base angles. The base angles= 53
All the angles of a triangle each 180, (the roof is shaped like a triangle)
So, let's make x the missing angle.
53(2)+x=180
106+x=180
Subtract 106 on both sides.
180-106= 74
The vertex angle is 74.
I hope this helps!
~cupcake
Answer:
Step-by-step explanation:
∠1 + ∠2 = 180 Linear pair
∠4 + ∠5 +∠ 3 = 180 form straight line
∠1 + ∠2 = ∠4 + ∠5 + ∠3 from statement 1 and 2
∠3 +∠2 = ∠4 + ∠5 + ∠3 ∠1 and ∠3 are vertically opposite angles.
∠2 = ∠4 + ∠5 Proved
Answer:
D
Step-by-step explanation: