Question

the sum of digits of a two digit number is 13. if sum of their squares is 89, find the number

Answer 1

[tex]Given: x+y=13 squaring both sides x^2+2xy+y^2=169 x^{2} + y^2=89 89+2xy=169 2xy=80 xy=40 x+y=13 , xy=40 i.e.,x=5 , y=8 [/tex]