You can put this solution on YOUR website! THE SUM OF THE ROOTS IS .5. I CARRIED ONE OF THE ANSWER OUT TO TOO MANY DECIMALS.
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2X^2-X=4
2X^2-X-4=0
USING TH E QUADRATIC EQUATION WE GET:
X=(1+-SQRT[(-1^2-4*2*-4])/2*2
X=(1+-SQRT[1+32])/4
X=(1+-SQRT33)/4
X=(1+-5.74456)/4
X=(1+5.74456)/4
X=6.74456/4
X=1.686 ANSWER.
X=(1-5.74456)/4
X=-4.74456/4
X=-1.18614 ANSWER.
SUM=1.686-1.186=.5 ANSWER FOR THE SUM OF THE ROOTS.