Question

why is formula for area of parallelogram and triangle same

Answer 1

no it is different
parallelogram has Base×height
triangle has 1/2×base×height

Answer 2

$\bf{No}$

The formula for area of parallelogram and triangle are different.

Area of parallelogram :
$\bf{base×height}$

Area of triangle :
$\bf{1/2×base×height}$