Respuesta :

Answer:

The number is 86

Step-by-step explanation:

Let the number be  [tex]xy[/tex], then the reverse is [tex]yx[/tex]

The sum of the reversed number and the original number is 154,

[tex]\implies (10x+y)+(10y+x)=154[/tex]

We simplify this to get:

[tex]\implies 11x+11y=154[/tex]....eqn(1)

If the ones digit in it is 2 less than the tens digit, then

[tex]y=x-2[/tex]....eqn(2)

Putt equation (2) in (1)

[tex]\implies 11x+11(x-2)=154[/tex]

[tex]\implies 11x+11x-22=154[/tex]

[tex]\implies 11x+11x=154+22[/tex]

[tex]\implies 22x=176[/tex]

[tex]\implies x=8[/tex]

Put x=8 in the second equation:

[tex]y=8-2=6[/tex]

The original number is 86

The original number is 86

[tex]\texttt{ }[/tex]

Further explanation

Simultaneous Linear Equations could be solved by using several methods such as :

  • Elimination Method
  • Substitution Method
  • Graph Method

If we have two linear equations with 2 variables x and y , then we need to find the value of x and y that satisfying the two equations simultaneously.

Let us tackle the problem!

[tex]\texttt{ }[/tex]

Let:

The original number = yx

The ones digit = x

The tens digit = y

[tex]\texttt{ }[/tex]

The ones digit in it is 2 less than the tens digit.

[tex]\boxed {x = y - 2}[/tex] → Equation 1

[tex]\texttt{ }[/tex]

The sum of the reversed number and the original number is 154.

[tex]xy + yx = 154[/tex]

[tex](10x + y) + (10y + x) = 154[/tex]

[tex]11x + 11y = 154[/tex]

[tex]\boxed {x + y = 14}[/tex] → Equation 2

[tex]\texttt{ }[/tex]

Equation 1 ↔ Equation 2 :

[tex]x + y = 14[/tex]

[tex]( y - 2 ) + y = 14[/tex]

[tex]2y - 2 = 14[/tex]

[tex]2y = 14 + 2[/tex]

[tex]2y = 16[/tex]

[tex]y = 16 \div 2[/tex]

[tex]y = 8[/tex]

[tex]x = y - 2[/tex]

[tex]x = 8 - 2[/tex]

[tex]x = 6[/tex]

[tex]\texttt{ }[/tex]

Conclusion:

The original number is 86

[tex]\texttt{ }[/tex]

Learn more

  • Perimeter of Rectangle : https://brainly.com/question/12826246
  • Elimination Method : https://brainly.com/question/11233927
  • Sum of The Ages : https://brainly.com/question/11240586

Answer details

Grade: High School

Subject: Mathematics

Chapter: Simultaneous Linear Equations

Keywords: Simultaneous , Elimination , Substitution , Method , Linear , Equations

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