the number of two digit is equal to four times the sum of digits. if the product of digits is 8 .find the number.

I think you are only intended to find

24

Explanation:

10x + y = 4(x + y)                         Remove the brackets

10x + y = 4x + 4y                         Subtract 4x from both sides

10x - 4x + y = 4x - 4x + 4y          Combine like terms

6x + y = 4y                                  Subtract y from both sides

6x + y - y = 4y - y                        Combine

6x = 3y                                        Divide by 3

6x/3 = 3y/3

2x = y

Put this result in the equation below

x*y = 8

x(2x) = 8

2x^2 = 8                                      Divide by 2

2x^2/2 = 8/2

x^2 = 4                                         Take the square root.

√x^2 = √4

x = ± 2

y = 2*x = ±4

Answer

The plus answer for x and y is the one we'll see about first.

10x + y = 20 + 4 = 24

24 =? 4(2 + 4)

24 =? 4*6 = 24

The product of it's digits = 2 * 4 = 8.

24 is definitely one answer.

What about -2 and - 4

-24 = 4(-2 + -4)

-24 = 4*-6 = -24

That works as well