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Use the Quadratic Formula to Solve the Equation: y = 7x2 - 14x - 56 a. x= - 4.35942. x = 2.35942 Selected:b. x = 4.18479 x = - 2.18479This answer is incorrect. c. x = 4, x = - 2 d. x = - 4 x = - 2

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Final answer:

To solve the equation using the quadratic formula, we identify a = 7, b = -14, and c = -56, then plug these into the formula to find two solutions, x = 4 and x = -2.

Step-by-step explanation:

To solve the quadratic equation y = 7x2 - 14x - 56 using the quadratic formula, we first need to write the equation in the standard quadratic form ax2 + bx + c = 0. For this equation, a = 7, b = -14, and c = -56. The quadratic formula is given by x = (-b ± √(b2 - 4ac)) / (2a).

Plugging the values into the quadratic formula:

x = (14 ± √((-14)2 - 4*7*(-56))) / (2*7)
x = (14 ± √(196 + 1568)) / 14
x = (14 ± √(1764)) / 14
x = (14 ± 42) / 14

Therefore, we have two solutions:

  • x = (14 + 42) / 14 = 56 / 14 = 4
  • x = (14 - 42) / 14 = -28 / 14 = -2

So, the solutions to the quadratic equation are x = 4 and x = -2.

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