Question

x+y =6;10y +x =10x +y= - 18 find two digit number​

Answer 1

Answer: Let the number with two digits be 10x + y

Given, the sum of the digits is 15

=> x + y = 15 ...........1

Number formed by reversing the digits = (10y + x)

According to the question,

     (10x + y) - (10y + x) = 27

=> 10x + y - 10y - x = 27

=> 9x - 9y = 27

=> 9(x - y) = 27

=> x - y = 27/9

=> x - y = 3   ..................2

Addaequation 1 and 2, we get

     x + y + x - y = 15 + 3

=> 2x = 18

=> x = 18/2

=> x = 9

Put value of x in equation 1, we get

     9 + y = 15

=> y = 15 - 9

=> y = 6

Therefore, the original number = 10(9) + 6

                                            = 10 * 9 + 6

                                            = 90 + 6

                                            = 96

Explanation: hope this will help you my friend

Answer 2

$\huge \color{red}ANSWER:$

Let x be units digit and y be the 10s digit

10y+x = 4(x+y)

10y + x = 4x +4y

6y-3x = 0

2y - x = 0 ————-(1)

When 18 is added to the number

10y + x +18 = 10x + y

Simplify

9y - 9x = -18

y - x = - 2

y = x - 2 —————-(2)

Substitute in equation #1

2(x-2) - x = 0

2x - 4 - x=0

x = 4

Substitute in equation#2

y = 2

There for the number is

2 x 10 + 4 = 24