Question 400347
If you are given the measure of the two legs of a right triangle, then you can find the length of the hypotenuse using the Pythagorean theorem.
Leg a = 9cm.
Leg b = 40cm.
Find c, the hypotenuse:
{{{c^2 = a^2+b^2}}} or...
{{{c = sqrt(a^2+b^2)}}} Substitute a = 9 and b = 40.
{{{c = sqrt(9^2+40^2)}}} Square the inside numbers.
{{{c = sqrt(81+1600)}}} Add.
{{{c = sqrt(1681)}}} Take the square root.
{{{c = 41}}}
Find the perimeter, P:
{{{P = a+b+c}}}
{{{P = 9+40+41}}}
{{{P = 90}}}cm
To find the area, use:
{{{A = (1/2)b*h}}} where b = base (9cm) and h = height (40cm). Substitute.
{{{A = (1/2)(9)(40)}}} Evaluate.
{{{A = 180}}}sq.cm.