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Question 186852: the tens digit of a two-digit number exceeds twice the units digit by 1. if the digits are reversed, the sum of the new number and the original number is 143. find the original number.
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! the tens digit of a two-digit number exceeds twice the units digit by 1.
if the digits are reversed, the sum of the new number and the original
number is 143. find the original number.
:
Let x = the 10's digit
Let y = the units
then
10x + y = the number
:
"the tens digit of a two-digit number exceeds twice the units digit by 1."
x = 2y + 1
or
x - 2y = 1
:
"if the digits are reversed, the sum of the new number and the original number is 143."
(10y + x) + (10x + y) = 143
10y + x + 10x + y = 143
11x + 11y = 143
Simplify, divide equation by 11
x + y = 13
:
Subtract the 1st equation
x + y = 13
x - 2y = 1
-------------eliminates x
0x + 3y = 12
y = 4
then
x = 2(4) + 1
x = 9
;
94 = the number
:
:
Check solution in the statement:
if the digits are reversed, the sum of the new number and the original number is 143.
49 + 94 = 143
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