Respuesta :

A equals 15

a^2+b^2=c^2

if the legs of  a right triangl measure a and b and the hypotonuse is c then
a²+b²=c²

hyptoonuse is opoiste right angle

we got tat the legs are a and 20
hyptonuse is 25

a²+20²=25²
a²+400=625
minus 400 both sides
a²=225
sqrt both sides
a=15