The answer is 515. Because 5×103 is 515
Answer:
46
Step-by-step explanation:
∠DAC ≅ ∠ACB because they are opposite interior angles where transversal AC crosses parallel lines BC and AD.
∠DAC ≅ ∠CAB because they are corresponding angles of the similar triangles ΔABC and ΔACD.
Hence ∠ACB ≅ ∠CAB and ΔABC is isosceles with side lengths both being 9. The corresponding side lengths of ΔACD are 12, meaning the base of ΔABC, segment AC, is 12. The scale factor of ΔACD to ΔABC is then 12:9 = 4:3, so the base AD of ΔACD is (4/3)×12 = 16.
So, the side lengths of the trapezoid are ...
- AB = 9
- BC = 9
- CD = 12
- DA = 16
and the perimeter is 9 +9 +12 +16 = 46 units.
Answer:
Measure of angle 4 is 115°
Step-by-step explanation:
First, we want to find the measure of angle 2, because the measure of angle 2 is equal to angle 4. When 2 straight lines cross each other, the angles formed are always equal to the angle right across from it.
Find angle 2 by setting up an equation:

This is basically saying that angle 1 plus angle 2 equals 180°. In a half turnaround, the angle is 180°. Angle 1 and 2 make up a half turnaround.
Solve the equation:

Combine the 2 x's to get 2x.

Subtract 50 from both sides.

Divide both sides by 2.

Since x=65, plug 65 into x in the measure of angle 2 (x+50).
65+50=115.
Since Angle 2 is equal to angle 4, angle 4 is also 115.