first you must find the measure of side C aka the hypotenuse using the Pythagorean theorem so
9^2 + 12^2 = C^2
81 + 144 = 225
sq root of 225 = 15 so the hypotenuse is 15cm
the triangle is dilated by 1.5 so multiply all sides by 1.5
a. 9 x 1.5 = 13.5
b. 12 x 1.5 = 18
c. 15 x 1.5 = 22.5
these are the new values for side abc
the perimeter(P) = a + b+ c
P= 13.5 + 18 + 22.5 = 54cm
