Question

Can someone help me on this question? As no one has got it correct
(Question in the image)

Answer 1

A = 11.5 cm²

Explanation:

the shaded area (A) is calculated as

A = area of outer square - area of 3 white right triangles

area of outer square = 5 × 5 = 25 cm²

area of left triangle =
`(1)/(2)` × 2 × 5 = 1 × 5 = 5 cm²

area of right triangle =
`(1)/(2)` × 3 × 4 = 1.5 × 4 = 6 cm²

area of lower triangle =
`(1)/(2)` × 5 × 1 = 2.5 × 1 = 2.5 cm²

Then

A = 25 - (5 + 6 + 2.5) = 25 - 13.5 = 11.5 cm²