Question

Im confusion? Could someone help me out.

Answer 1

20cm

Explanation:

for the triangle:

Perimeter = 30cm

a + a + a = 30

3a = 30

hence a = 10cm

For the rectangle:

Perimeter = 30cm

a + a + b + b = 30

but a = 10cm

10 + 10 + b + b = 30

20 + 2b = 30

2b = 10

hence b = 5cm

Perimeter of square = b + b + b + b

= 5 + 5 + 5 + 5 = 20cm