Posted by Anonymous on Thursday, February 28, 2013 at 9:50pm.
The sum of the digits of a certain two-digit number is 7. Reversing its digits increase the number by 9. What is the number. Use x and y. Please help me!!!!
- algebra - Reiny, Thursday, February 28, 2013 at 10:54pm
in the original number, let the unit digit be x, then tens digiti be y
so the original number is 10y + x
where x+y = 7
the number reversed will be 10x + y
new number - old number = 9
10x + y - (10y + x) = 9
9x - 9y = 9
or x-y = 1
2x = 8
x = 4, then y = 3
the number is 10y+x = 34
original number is 34
reversed number is 43
is the number increased by 9 ??? YES
is the sum of the digits 7 ??? YES
Answer This Question
More Related Questions
- 8th Grade Algebra - These are extra credit questions, and I just want to know ...
- algebra word prob. - one more - The sum of the digits of a certain two-digit ...
- Algebra - When you reverse the digits in a certain two digit number you ...
- Algebra math. - 1) the sum of the digits of a two digit number is 9. The value ...
- algebra - The value of a certain two-digit number is eight times he sum of its ...
- Algebra 1--Please, help me! - 4. The sum of the digits of a two-digit number is ...
- Maths - The digits of a three digit number are in AP&their sum is 15.The number ...
- math ALGEBRA - When the digits of two-digits numbers are reversed, the new ...
- Math - The sum of the digits of a two-digit number is 14. The number formed by ...
- Algebra - A number consist of 3 digits.The middle digit is 0 and the sum of the...