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Can someone solve this equation for me stomped

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5 Answers

2x^2+14x=88
subtract 88 from both sides
2x^2+14x-88=0
divide both sides of the equation by 2 to get x^2+7x-44=0
the equation is in the form ax^2+bx+c=0
a and b are both odd, (1 and 7)
therefore c(-44) must be factored into an odd number times an even number, NOT an even times an even
therefore you can't use 2 and 22, you must use 1 and 44 or 4 and 11(disregarding signs for the moment)
does adding 11 and 4 or subtracting 11 and 4 give you 7 ?  YES, 11-4=7
-44=(4)(-11) or (-4)(11)
the coefficient of x must be +7, so you can't  use 4 and -11(-11+4=-7)
you must use -4 and 11 because 11+(-4)=7
therefore you get 2(x+11)(x-4)=0
x+11=0 and x-4=0
x=-11 and x=4
 
 
First, divide both side by 2. You will get:
 
x2+7x=44 or
x2+7x-44=0;
 
You may use factoring. Two factors that multiply to get -44 are -11 and 4. Their sum shall be equal to coefficient in front of x, but with opposite sign. Indeed, -11+4=-7, just as it should be.
 
So the trinomial can be factored as follows:
x2+7x-44=(x+11)(x-4); If (x+11)(x-4)=0 then x=-11 or x=4.
2x2 +14x =88
 
1. First subtract 88 from both sides so that the equation is equal to 0.
    2x2 +14x - 88 = 0
 
2. Find the Highest Common Factor (HCF) that can be divided into each term
    in the trinomial.
    2 (x2 +7x - 44) = 0
 
3. Factor the remaining trinomial.
        2 (x2 +7x - 44) = 0
    a. Find the pairs of factors of the third term -44 = -4,11 or 4, -11;
        -2,22 or 2, -22; -1,44, 1,-44;
    b. Choose the pair of factors that when added together give +7,
        the coefficient of the middle term. These are -4 and +11.
        2 (x - 4)( x + 11) = 0
 
4. Finally use the zero product property to solve the equation.
    x - 4 = 0     |      x + 11 = 0
    x = 4          |       x = -11
 
 
 
 
 
 
 
 
 
 
 

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