PERIMETER: First you’ll find the second leg for the smaller triangle by using the pythagorean theorem (a^2 + b^2 = c^2)
3^2 + b^2 = 5^2
=4 cm
Then you’ll use this number to find the hypotenuse of the larger triangle,
15^2 + 4^2 = c^2
which comes out to about 15.52 cm
Perimeter (shaded/large) = 34.52 cm
Perimeter (small) = 12 cm
Perimeter (total) = 46.52 cm
AREA:
We will be using the formula for the area of a triangle here (b*h/2)
Area (large) = (4*15)/2 = 30 cm
Area (small) = (3*4)/2 = 6 cm
Area (total) = 30+6 = 36 cm
OR ((15+3)*4)/2= (18*4)/2 = 36 cm
