Answer:
x = 12
Step-by-step explanation:
Supplementary angles, sum = 180
10x - 20 + 6x + 8 = 180
16x - 12 = 180
16x = 192
x = 12
Answer:
isosceles trapezoid
Step-by-step explanation:
1) find the distance of the points

AB = 
BC = |7-4| = 3
CD = 
AD = |9-2| = 7
2) equation of the line that passes threw BC
y = 7
3) equation of the line that passes threw AD
y = 5
conclusion
the quadrilateral has two parallel sides and two congruent sides, so it is a isosceles trapezoid
The distance formula is sqare root (x-x)^2+(y-y)^2 and then you will plug in
sqrt(8+13)^2+(4+5)^2
plug that in to your calculator and that will be your answer what ever you get