If the height of a triangle is decreased by 40% and its base is increased by 40% what will be the effect on its area?

A. No change
B. 8%decrease
C. 16% Decrease
D. 16%increases

Explanation:

let the height be ‘h’ and base = b, then area =(1/2 bh)sq.units

New height =(60 % of h) = (60/100 h) = 3h/5

New base =(140% of b) =(140/100 b) =(76/5)

New area =(1/2 x 7b/5 x 3h/5) Sq.units =(21/50 bh)sq.units

Decrease in area =(1/2bh – 21/50bh)= 4/50 bh

Decrease % =(4/50bh. 2/bh x 100)% =16%