SOLUTION: what do I need to do to solve problem written find two numbers whose product is 7 and whose sum is 8

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Question 470957: what do I need to do to solve problem written find two numbers whose product is 7 and whose sum is 8
Found 2 solutions by Tatiana_Stebko, lwsshak3:
Answer by Tatiana_Stebko(1539) About Me  (Show Source):
You can put this solution on YOUR website!
Let x and y are two numbers
system%28x%2Ay=7%2Cx%2By=8%29
from the second equation y=8-x
x%288-x%29=7
8x-x%5E2-7=0multiply by (-1)
x%5E2-8x%2B7=0
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-%28-8%29+%2B-+sqrt%28%28-8%29%5E2-4%2A1%2A7+%29%29%2F%282%2A1%29+
x+=+%288+%2B-+sqrt%2836+%29%29%2F2+
x1+=+%288+%2B6+%29%2F2+=7
x2+=+%288+-6+%29%2F2+=1
if x1=7, then y1=8-7=1 => (7,1)
if x2=1, then y2=8-1=7 => (1,7)
Answer these numbers are 1 and 7

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
what do I need to do to solve problem written find two numbers whose product is 7 and whose sum is 8
**
let x= one of the numbers
let y= other number
..
x+y=8
y=8-x
x*y=7
x(8-x)=7
8x-x^2=7
x^2-8x+7=0
(x-7)(x-1)=0
x=7
and
x=1
ans:
The numbers are 1 and 7