find the area of the triangle on top
A=(.5)(Base)(Height)
A=(.5)(15)(9)
A=67.5
In the rhombus below you can move the corner triangle to the other side to transform it into a rectangle with a sides of 7 and 15. so lets find the area of this rectangle
A=LW
A=157
A=105
now combine the two areas
67.5+105
172.5
so answer "C"
