Question 107082
draw a picture of the trapezium and label in the information we know. Let CD=x

So if CD=x, AB=1.5x and the other two sides are equal to 13.

An expression for the perimeter would be the sum of all four of these sides

P=x+1.5x +13+13
make this equal to 76
x+1.5x +13+13=76
2.5x+26=76
2.5x=76-26
2.5x=60
x=60/2.5
x=24

so cd= 24
cb=1.5x
=1.5*24
=36


Now for the area:
Area= 1/2 x height x sum of base length
height=12
sum of base lengths is 24+36=60

Area=0.5*12*60
=360cm^2