Answer :
a^2 +b^2 = c^2
a= wall
b = ground (18)
c = ladder (25)
a^2 + 18^2 = 25^2
a^2 + 324 = 625
a^2 = 301
a = 17.349
a= wall
b = ground (18)
c = ladder (25)
a^2 + 18^2 = 25^2
a^2 + 324 = 625
a^2 = 301
a = 17.349