|
Question 932696: The sum of the digits of a certain two digit number is 7. Reversing it's digits increases the number by 9. What is the number?
Answer by TimothyLamb(4379)   (Show Source):
You can put this solution on YOUR website! x = ones digit
y = tens digit
---
x + y = 7
10x + y = x + 10y + 9
---
put the system of linear equations into standard form
---
x + y = 7
9x - 9y = 9
---
copy and paste the above standard form linear equations in to this solver:
https://sooeet.com/math/system-of-linear-equations-solver.php
---
solution:
x = ones digit = 4
y = tens digit = 3
---
answer:
the number, by observation = 34
the number, by algebra = x + 10y = 4 + 10*3 = 34
---
Solve and graph linear equations:
https://sooeet.com/math/linear-equation-solver.php
---
Solve quadratic equations, quadratic formula:
https://sooeet.com/math/quadratic-formula-solver.php
---
Solve systems of linear equations up to 6-equations 6-variables:
https://sooeet.com/math/system-of-linear-equations-solver.php
---
|
|
|
| |
