Question

the sum of two digit number is 9 .If 45 is added to the number , the digit are interchanged . Find the number?
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Answer 1

Answer:

Don't mark me brainiest.

let the unit please be y and tens be x

original number be 10x + y ,

x+y=9,

and to find the second equation

10x +y+45 =10y+ x

9(x-y)=-45

x-y=-5

x+y=9

x-y=-5

--------------------- cuts the y

2x. =4

,x=2

now putting the value of x into y

2+y=9

,y=7