Question

13 The sum of the digits of a 2-digit number is 7. If the digits are
reversed, the number formed is 9 less than the original number. Find
the number.​

Answer 1

Answer:

Step-by-step explanation:

let the digits be x and y of a number

x + y =7 (1) [ because always the digit written in ten place is multiplied by 10]                                                

ORIGINAL NO. =>10x+y

REVERSED NO. =>10y+ x

10x + y - (10y+x) = 9

10x+y -10y-x =9

9x-9y = 9

x-y=1 (2)

Add both the equations

2x =8

x=4

x+y=7

4+y = 7

y=3

Answer 2

Answer:

43

Step-by-step explanation:

Let x be Ten's place digit and y be the One's place digit

So, x+y=7------(i)

and (10x+y)-(10y+x)=9

=>x-y=1-------(ii)

Adding Eqn (i) and (ii) we get:-

x=4

So, y=3

Therefore, original number is 43