Question

A number consists of two digits in the tens places is the square of the digit in the unit place, the sum of the digits id 12. Find the number.​

Answer 1

Solution:

let the number 10x+y....[x is the digit at unit's place and y is the digit at ten's place.]

now,

y= x^2.....(1)

also,

x+y= 12

hence,

y= 12-x.....(2)

substituting the value of y in (1),

12-x=x^2

x^2+x-12=0.....required quadratic equation.

now,

by factorization method,

x^2+4x-3x-12=0

x^2-3x+4x-12=0

x(x-3)+4(x-3)=0

(x-3)(x+4)=0

therefore,

x=3 or x=-4

but digits cannot be negetive so x=-4 is discarded.

hence,

x=3

substituting this value in (2)

y= 12-x

y= 12-3=9

hence,

number= 10x+y= 9+10×3= 30+9=39

hope this helps!!❤✌☺

Answer 2

Answer:

Step-by-step explanation: