Question

ABDE is a rectangle

ED is 8cm

BCD is a right-angle triangle
BC is 4.5cm

ABC is a straight line

The area of the rectangle ABDE is 40cm squared
Work out the area of the triangle BDC

Answer 1

11.25 cm²

Explanation:

Area of rectangle = height * length = ED*BD

40 cm² = 8cm * BD

BD = 5cm

Area of triangle = 1/2 length * height = 1/2 *BC*BD

= 1/2 * 4.5 *5

= 11.25 cm²