SOLUTION: WHAT TWO NUMBERS ADDED TOGHER EQUAL FIVE AND MULTIPLIED TOGETHER EQUAL NINE

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Question 163727: WHAT TWO NUMBERS ADDED TOGHER EQUAL FIVE AND MULTIPLIED TOGETHER EQUAL NINE
Answer by ptaylor(2198) About Me  (Show Source):
You can put this solution on YOUR website!
Let x=one number
And y= the other number
x+y=5-----------eq1
x*y=9------------eq2
Divide both sides of eq2 by y
x=9/y---------------substitute into eq1
(9/y)+y=5 multiply each term by y
9+y^2=5y subtract 5y from each side
y^2-5y+9=0 ----quadratic in standard form. Solve using quadratic formula
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%285+%2B-+sqrt%28%28+-5%29%5E2-4%2A1%2A9+%29%29%2F%282%29+
x+=+%285+%2B-+sqrt%28%2825-36%29%29%29%2F%282%29+
x+=+%285+%2Bi%2Asqrt%2811%29%29%2F%282%29+ ------------------one number
x+=+%285+-i%2Asqrt%2811%29%29%2F%282%29+ ----------the other number
CK
(5 +i*sqrt(11))/(2)+(5 -i*sqrt(11))/(2)=10/2=5
And
{(5 +i*sqrt(11))/(2)}*{(5 -i*sqrt(11))/(2)}=25/4 +11/4=36/4=9

Hope this helps---ptaylor