Question

If the height of a triangle is decreased by 40%
and its base is increased by 40%, what will be
the percentage change in its area ? pls help me i will as brainlist. ​

Answer 1

Question :

• If the height of a triangle is decreased by 40% and its base is increased by 40%, what will be the percentage change in its area ?

To find :

• Percentage change in its Area.

Let :

• Height be h.

• Base be b.

Answer :

Area = $\bf\dfrac{1}{2}$ bh

New height = h - $\bf\dfrac{40}{100}$ h

⠀⠀⠀⠀⠀⠀⠀⠀= $\bf\dfrac{60h}{100}$

New base = b + $\bf\dfrac{40}{100}$ b

⠀⠀⠀⠀⠀⠀⠀⠀= $\bf\dfrac{140b}{100}$

New area = $\bf\dfrac{1}{2}$ × $\bf\dfrac{60}{100}$ × $\bf\dfrac{140}{100}$ bh

⠀⠀⠀⠀⠀⠀⠀⠀= $\bf\dfrac{1}{2}$ $\bf\dfrac{84}{100}$ bh

⠀⠀⠀⠀⠀⠀⠀⠀= $\bf\dfrac{1}{2}$ (bh - $\bf\dfrac{16}{100}$ bh)

Decreased by 16%.