Bring terms together: First, we need to bring all terms to one side of the equation to set it equal to zero. We do this by subtracting x from both sides of the equation.−6x2+6−2x−x=0This simplifies to:−6x2−3x+6=0
Solve quadratic equation: Next, we need to solve the quadratic equation. We can do this by using the quadratic formula, which is x=2a−b±b2−4ac, where a, b, and c are the coefficients from the quadratic equation ax2+bx+c=0. In our case, a=−6, b=−3, and c=6.
Plug values into formula: Now we will plug the values of a, b, and c into the quadratic formula.x=2(−6)−(−3)±(−3)2−4(−6)(6)This simplifies to:x=−123±9+144x=−123±153
Simplify square root: We simplify 153 to get the exact values for x. 153 is not a perfect square, so we leave it as is. x=−123±153
Divide by common divisor: We can simplify the fraction by dividing the numerator and the denominator by their greatest common divisor, which is 3 in this case.x=(1±153/3)/(−4)Since 153/3 is not a simplifiable square root, we leave it as is.x=(1±153/3)/(−4)
Match with answer choice: Now we look at the answer choices to see which one matches our result. We notice that 153 is the same as (17⋅9), which simplifies to 317. So our equation becomes:x=(−4)(1±317)This matches answer choice (D).
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