Math, asked by mahikumari0376, 1 month ago

a number of two digits has the sum of its digits as 7 when 9 is subtracted from the number, digits are reversed.the number is​

Answers

Answered by ItzBrainlyLords
3

Solving :

  • Let digits at tens place be = x

  • Digits at ones place = y

  \\  \large \sf \therefore \: number = 10x + y \\  \\  \large \sf \mapsto \: reversed \:  \: number = 10y + x \\  \\  \large \star \underline{ \underline{  \sf \: according \:  \: to \:  \: question : }} \\  \\ \large \sf \: x + y = 7 \longrightarrow(i)\\  \\  \large \tt  : \implies \: 10x + y - 9 = 10y + x \\  \\  \large \tt  : \implies \: 10x  - x  +   y   -  10y = 9\\  \\  \large \tt  : \implies \: 9x - 9y = 9 \sf \longrightarrow(ii) \\  \\

 \large \rm \mapsto \underline{ \underline{ \rm \: by \:  \: elimination \:  \: method : }} \\  \\  \large \sf \: 9x - 9y = 9 \\  \\  \large \sf  : \implies \: 9(x + y = 7) \\  \\   \large \sf  : \implies \: 9x + 9y = 63\\  \\   \large \rm \: adding \:  \: equations : \\  \\  \\   \large \sf  : \implies \: 9x +  \cancel{9y} = 63\\    \large \sf   +  \:  \: \: 9x \:   \cancel{- 9y} = 9 \\  \\ \\   \large \sf  : \implies \: 18x = 72\\  \\  \\   \large \sf  : \implies \: x =  \frac{72}{18} \\  \\   \large \boxed{ \sf  \therefore \: x = 4}\\  \\

 \large \sf \: x + y = 7 \\  \\ \large  \implies\sf \: 4 + y = 7 \\  \\  \implies\large \sf \:  y = 7  - 4\\  \\  \large \boxed{ \sf  \therefore \: y = 3}\\  \\

 \large \sf number = 10x + y \\  \\  \large \sf \implies \: 10(4) + 3 \\  \\  \large \sf \:  =  \: 40 + 3

Number = 43

Answered by neerajnegi353
2

Answer:

hi my name is Neeraj

Step-by-step explanation:

me 16 years ka hu

what is your name

Kya aap Meri friend banogi agrar yes to 5 star Dena

Similar questions