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Quadriatic formula 2w^2-28w=-98

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2w^2-28w=-98
w^2-14w+49=0D=14^2-4*49=0
w=(14+0)/2=7


User Mou
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1 vote
To apply the quadratic formula, the right side must be equal to 0.


2w^2-28w=-98 \\ 2w^2-28w+98=0

Now you can apply the quadratic formula
(-b\±√(b^2-4ac))/(2a) to find the solution for w.


(-(-28)\±√((-28)^2-4(2)(98)))/(2(2)) = (28\±√(784-784))/(4) = \frac{28}4 = \boxed{7}

(The quadratic formula is highly unnecessary in this problem, however. You could easily divide all values by 2 to get w²-14w+49=0, which factors into (w-7)²=0, for which 7 is the only solution which puts a factor of the quadratic equal to 0.)


User WaterFox
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