SOLUTION: Question 1: The sum of two numbers is 15 and their difference is 9. Find the two numbers.

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Question 797126: Question 1: The sum of two numbers is 15 and their difference is 9. Find the two numbers.
Answer by mohanraj04(12) About Me  (Show Source):
You can put this solution on YOUR website!
given that
the sum of two numbers is 15 and difference of two numbers is 9
let X & Y be the two numbers
EQU:1 X+Y=15;
EQU:2 X-Y=9
ADD EQU:1 AND EQU:2
(X+Y)+(X-Y)=15+9
2X=24
X=24/2
X=12
substitute X=12 in equ:1
X+Y=15
12+Y=15
Y=15-12
Y=3
therefore the required two numbers are 12 & 3
to check
12+3=15
12-3=9