Question

see question number 4 and answer

Answer 1

area of the triangle = 90cm^2
height = 12cm
area of the triangle = 1/2 × b × h
90 = 1/2 × b × 12
90 × 2/12 = b
180/12 = b
15 = b

base = 15 cm

Hope it helps....❤❤

Answer 2

$\textbf{area=b×h 90=12×h h=7.5}$