Respuesta :
X is the second side. Side 1 is s-5. side 3 is s-2 (s-5+3). They all must add up to 17. Well there is your answer right there. S-2
P = a + s + c....a = 1st side, s = 2nd side, c = 3rd side
a = s - 5
c = a + 3......c = s - 5 + 3 = s - 2
so ur answer is : s - 2
a = s - 5
c = a + 3......c = s - 5 + 3 = s - 2
so ur answer is : s - 2