Answer:
Step-by-step explanation:
If the diagonals of the rectangle are congruent,
AC = BD
By using formula to calculate the distance between two points,
Distance between two points = 
Distance between A(0, -3) and C(2, 8),
AC = 
= 
= 
Similarly, distance between two points B(-4, 0) and D(6, 5),
BD = 
= 
= 
Therefore, both the diagonals are congruent.
Hence, given quadrilateral ABCD is a rectangle.
Answer:
34
Step-by-step explanation:
A triangle will add up to a degree of 180, so if you add those 2 angles then subtract it from 180 you will get the answer. So, 115+31=146 then 180-146=34
So the answer is 34
Answer:

24x = 8*60
24x = 480
x = 20
Step-by-step explanation:
Last choice the area becomes 25 times greater
Answer:
18, -3
using the formula for midpoint M=(x1+x2)/2 ,(y1+y2)/2