A rectangle is inscribed with congruent isosceles triangles, a portion of which shown. The verticals of the triangles are the height of the rectangle. If the bases of four triangles span the base of the rectangle, and the ratio of the base to the height of each of the triangles is 4:7, the area of the rectangle, in terms of base b of a triangle, is
a) 7/4 b
B) 8b
C) 4 (b+7) ^ 2
D)7 b ^2
E) 8 b^2
a) 7/4 b
B) 8b
C) 4 (b+7) ^ 2
D)7 b ^2
E) 8 b^2
