Math ? 4 questions. i would really appreciate it. ( 40 pts)

1st pic

It's a rhombus
 - None of the angles are 90 degrees (can't not be rectangle or square)
 - Opposite angles are equal

Top triangle 
180 - ( 72 + 72 )
=180 - 144
= 36

same as bottom triangle

2nd pic.

Rhombus...
opposite angles are equal
so m<1 = m<2 = 160

180 - 160 = 20

m< 3 = 20/2 = 10

answer
m<2 = 160
m<3 = 10

3rd pic.
 isosceles trapezoid

The legs are congruent by definition

so AB = CD
7y - 4 = 8y - 18
7y - 8y = -18 + 4
- y = -14
y =14

answer y = 14


pic 4

A(-5, -1), B(-9, 6) C (-1, 5) D(3,-2)

A(-5, -1) and C (-1, 5) ---find slope of 1st pair
slope = (5 + 1)/(-1 + 5) = 6/4 = 3/2

B(-9, 6)  D(3,-2)---find slope of 2nd pair
slope = (-2 -6)/(3+9) = -8/12= -2/3

slope of 2nd pair (-2/3) is negative and reciprocal of the 1st pair (3/2)

so it's perpendicular