Move terms to one side: Write the equation in standard form by moving all terms to one side.We want to get the equation into the form ax2+bx+c=0.3x=9x2−100=9x2−3x−10What are the values of a, b, and c?a=9, b=−3, c=−10
Write equation in standard form: Use the quadratic formula to solve for x.The quadratic formula is x=2a−b±b2−4ac.Substitute a=9, b=−3, and c=−10 into the quadratic formula.x=2⋅9−(−3)±(−3)2−4⋅9⋅(−10)
Values of a, b, and c: Simplify the equation.x=183±9+360x=183±369
Use quadratic formula: Calculate the discriminant (the value inside the square root). 369 is the discriminant.
Substitute values into formula: Find the two possible solutions for x.x=183+369 or x=183−369
Simplify equation: Simplify the square root. 369 is approximately 19.21. x=183+19.21 or x=183−19.21
Calculate discriminant: Calculate the two solutions.x≈(3+19.21)/18 or x≈(3−19.21)/18x≈22.21/18 or x≈−16.21/18x≈1.23 or x≈−0.90
Find possible solutions: Check the solutions against the answer choices.None of the answer choices match the solutions we found.
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