SOLUTION: the sum of two numbers is 11 and their difference is 6. find the number

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Question 927118: the sum of two numbers is 11 and their difference is 6. find the number

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

the sum of two numbers, x and y, is 11 and their difference is 6
x%2By=11...eq.1
x-y=6....eq.2
______________________
start with
x%2By=11...eq.1..solve for y
y=11-x...substitute in eq.2

x-%2811-x%29=6....eq.2.solve for x

x-11%2Bx=6

2x=6%2B11
2x=17
x=17%2F2
highlight%28x=8.5%29
now find y

y=11-x
y=11-8.5
highlight%28y=2.5%29

check:
x%2By=11...eq.1=>8.5%2B2.5=11=>11=11
x-y=6....eq.2=>8.5-2.5=6=>6=6