Let the consecutive natural numbers be (x) and (x+1) Sum of squares = (x)2+(x+1)2=145 ⇒ x2+x2+2x+1=145 ⇒ 2x2+2x−144=0 ⇒ x2+x−72=0 ⇒ x2+9x−8x−72=0 ⇒ x(x+9)−8(x+9)=0 ⇒ (x−8)(x+9)=0 ⇒ x=8,−9 Since, x is a natural number, it can't be negative. ∴ The natural numbers are 8 and 9