Westonci.ca offers quick and accurate answers to your questions. Join our community and get the insights you need today. Discover comprehensive solutions to your questions from a wide network of experts on our user-friendly platform. Our platform provides a seamless experience for finding reliable answers from a network of experienced professionals.

Find a two-digit number such that three times the tens digit is 2 less than twice the units digit, and twice the number is 20 greater than the number obtained by revers- ing the digits.​

Sagot :

Answer:

  47

Step-by-step explanation:

You want a two-digit number such that three times the tens digit is 2 less than twice the units digit, and twice the number is 20 greater than the number obtained by reversing the digits.

Setup

Let x and y represent the tens digit and ones digit, respectively. The given relations can be written as equations as follows:

  3x = 2y -2 . . . . 3 times tens digit is 2 less than 2 times ones digit

  2(10x+y) = (10y +x) +20 . . . . 2 times the number is 20 more than reversed

Solution

Simplifying the equations and expressing them in standard form, we have ...

  3x -2y = -2

  20x +2y = x +10y +20   ⇒   19x -8y = 20

Subtracting 4 times the first equation from the second, we have ...

  (19x -8y) -4(3x -2y) = (20) -4(-2)

  7x = 28 . . . . . . . simplify

  x = 4

Substituting into the first equation, we have ...

  3(4) -2y = -2

  12 +2 = 2y . . . . . add 2y+2

  7 = y . . . . . . . . divide by 2

The two-digit number is 47.