Answer:
6(2a+4)-4(3a-4)= (12a+24) +(-12a+16) = 40
Http://www.pierce.ctc.edu/staff/dlippman/mathinsociety/Finance1.0.pdf I think this will help
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.
Use calcutlator and it all smushed up i can barley see it