Question

a 2 digit number is such that the product of its digit is 18 and when 63

Answer 1

Answer:

And the units place digit be y. Hence, the required number is 92

Step-by-step explanation:

Let the number be 10x+y

According to question,

10x+y−63=10y+x

⇒10x−x+y−10y=63

⇒9x−9y=63

⇒x−y=7

⇒x=7+y (i)

xy=18 (ii)

Substituting the value of x in (ii) we get,

(7+y)y=18

⇒y

2

+7y−18=0

⇒y

2

+9y−2y−18=0

⇒y(y+9)−2(y+9)=0

⇒(y+9)(y−2)=0

⇒y=−9 and y=2

y=−9 is not valid

∴y=2

Putting the value of y in (i) we get,

x−2=7

⇒x=7+2

⇒x=9

So the number =10x+y=10(9)+2=92