SOLUTION: The tens digit of a certain two-digit number exceeds the units digit by 3. The sum of the digits is 1/7 of the number. Find the number.

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: The tens digit of a certain two-digit number exceeds the units digit by 3. The sum of the digits is 1/7 of the number. Find the number.      Log On


   



Question 667738: The tens digit of a certain two-digit number exceeds the units digit by 3. The sum of the digits is 1/7 of the number. Find the number.
Answer by ReadingBoosters(3246) About Me  (Show Source):
You can put this solution on YOUR website!
Establish the variables
x = tens place
y = ones place
...
Given
x = y+3
x+y = 1%2F7(10x+y)
...
Substitute x into the equation
y+3 + y = 1%2F7(10(y+3) + y)
...
Distribute the 10
2y + 3 = 1%2F7(10y + 30 + y)
...
Combine like terms
2y + 3 = 1%2F7(11y + 30)
...
Multiply both sides by 7 to be rid of the fraction
14y + 21 = 11y + 30
Isolate y
14y - 11y = 30 - 21
3y = 9
highlight_green%28y=3%29
...
x = y+3 = 3+3
highlight_green%28x=6%29
...
Then number is highlight%2863%29
...
Check cartoon%28%0D%0A%281%2F7%29%2A%2863%29+=+9%2C%0D%0A6%2B3=9%29
.....................
Delighted to help.
-Reading Boosters
Wanting for others what we want for ourselves.
www.MyHomeworkAnswers.com