SOLUTION: x+y= 18 x*y= 56 We've figured out the values of x and y are 14 and 4, but we have stalled trying to prove our answer algebraicly, I.e. to "show our work." Can you help, p

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Question 662458: x+y= 18
x*y= 56
We've figured out the values of x and y are 14 and 4, but we have stalled trying to prove our answer algebraicly, I.e. to "show our work."
Can you help, please?
Found 3 solutions by ReadingBoosters, Alan3354, MathLover1:
Answer by ReadingBoosters(3246)   (Show Source):
You can put this solution on YOUR website!
Starting with
x+y=18
x*y=56
Rearrange one of the equations to solve for one variable
x=18-y
use this in substitution within the other equation
(18-y)y=56
18y - y^2 = 56
Subtract by 18y and y^2 on both sides
0 = 56 - 18y + y^2
Rearranging the quadradic equation
y^2 - 18y +56 = 0
(y-14)(y-4)
y-14=0 so y=14
y-4=0, so y=4
..........................
Delighted to help
-Reading Boosters

Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website!
x+y= 18
x*y= 56
-----------
y = 18 - x
Sub for y
x*(18 - x) = 56

x = 4, x = 14

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

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