SOLUTION: Find two factors of 28 with a sum of 11.

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Question 91796: Find two factors of 28 with a sum of 11.
Answer by mathispowerful(115) About Me  (Show Source):
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according to the problem:
assume the two factors are x and y
then x + y = 11
x*y = 28
a quadratic equation can be formed:
from the first equation y = 11 - x
substitute y:
x%2A%2811+-+x%29=+28
11x+-+x%5E2+=+28
or x%5E2+-+11x+%2B28+=+0
solve this equation: (x -4)(x - 7) = 0
so x = 4 and x = 7
the corresponding y values are y =7 and y = 4.
The answer the two factors are 4 and 7.