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The product of a number decreased by 3 and the same number increased by 8 is 80.

1 Answer

5 votes

Answer:

-13, 8

Explanation:

(x-3)(x+8) = 80

use FOIL to eliminate parenthesis

x² +8x - 3x - 24 = 80

combine like terms

x² + 5x - 24 = 80

move the constant to the left

x² + 5x - 104 = 0

factor x and then factor -8

x(x+13) - 8(x+13) = 0 factor (x+13)

(x+13)(x-8) = 0

separate into possible cases

x + 13 = 0

x - 8 = 0

solve

x = -13

x = 8

have a lovely day <3

User Anubian Noob
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