# What 2 numbers have a sum of 25 and a product of 136?

2
by danielgonz09

2014-11-20T19:34:28+08:00
Let 'x' be the first number
'y' be the other number
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-Their sum is 25
x + y = 25    -----equation 1
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-Their product is 136
x(y) = 136   ----equation 2
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From equation 1:
x + y = 25
x = 25 - y -----equation 1'
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Substitute equation 1' to equation 2
x(y) = 136
(25-y)y = 136
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Distribute y to the quantity (25-y)
25y - y² = 136
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Transpose 25y - y² to the right side of the equation
y² - 25y + 136 = 0
(y-17)(y-8) = 0
y=17; y=8
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If y=17
Using equation 1'
x = 25 - y
x = 25 - 17
x = 8
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If y=8
Using equation 1'
x = 25 - y
x = 25 - 8
x = 17
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Therefore the two numbers are 8 and 17.

OR
You can have it this way: =)
FACTORS of 136
136 = 1 x 136
136 = 2 x 68
136 = 4 x 34
136 = 8 x 17
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From the factors, choose the ones when added will have a sum of 25
In which case is the pair 8 and 17.
2014-11-20T20:19:13+08:00
The two numbers are 17 and 8