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fivegrays fivegrays
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11 years ago
The equation is: (x+1)(x-2)=4....
Please solve it step by step...
Thank you
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#1
11 years ago
Honestly... all you have to do is know that x>2 so that you can get a number that's not negative... since (2+1)(2-2)=0
Plug in three to the equation and you get (3+1)(3-2) which is equal to (4)(1) which is 4
wrote...
#2
11 years ago
FOIL it out.

x²-2x+x-2 = 4

Combine like tems
x²-x-6 = 0

What multiplies to -6 and adds to -1? -3 and a positive 2

(x-3)(x+2)

x-3 = 0
x+2 = 0

x = -2 and x = 3
wrote...
#3
11 years ago
Expand using FOIL or whatever

(x+1)(x-2)=4

x^2 - x - 2 = 4

Move the 4 across so that it's an ordinary trinomial/quadratic

x^2 - x - 6 = 0

(x + 2)*(x - 3) = 0

x = -2 or x = 3
wrote...
#4
11 years ago
(x + 1)(x ? 2) = 4

x² + x ? 2x ? 2 = 4

x² ? x ? 2 = 4

x² ? x ? 2 ? 4 = 0

x² ? x ? 6 = 0

x² ? 3x + 2x ? 6 = 0

x(x ? 3) + 2(x ? 3) = 0

(x ? 3)(x + 2) = 0

[ x = 3 , ? 2 ]

Hope this helps
Bye !!
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