Question

In a two digit number, the product of the digit is 12 and the sum is 7. Fiz a number.​

Answer 1

The two digit number could be 43 or 34.

Explanation:

Let xy be the two digit number

xy = 12

x = 12/y ---equation 1

x + y = 7 ---equation 2

Plug in equation 1 to equation 2

x + y = 7

(12/y) + y = 7

Multiply the whole equation by y

12 + y² = 7y

Transpose

y² - 7y + 12 = 0

(y - 4)(y - 3) = 0

y - 4 = 0

y = 4

y - 3 = 0

y = 3

When y = 4 Substitute the value to equation 1

x = 12/y

x = 12/4

x = 3

When y = 3

x = 12/3

x = 4

Since 2 values of x and 2 values of y satisfy the conditions then the number is either 43 or 34.