Question

A two digit no is made of two consecutive digits such that sum of squares for number is 4 less than the number. Find the number

Answer 1

Answer:

4,5

Step-by-step explanation:

let the digits be x&y

ie., the no. is 10x + y

given, y = x+1    ------- i    (∵ they are consecutive no.s)

  also, x²+y² = 10x+y-4 --------- ii  (condition 2)

substitute i in ii , we get

x² + (x+1)² = 10x+(x+1)-4

x²+x²+2x+1 = 11x-3

2x²+2x-11x+1+3 = 0

2x²-9x+4=0

on factorising , we get

(2x−1)(x−4)=0

=> 2x-1 = 0 => x= 1/2  (not possible)

or x-4 = 0 > x = 4

y = 4+1 by i

y=5