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2 years ago

Solve the quadratic equation 2x2 – x = 15 using the quadratic formula.

Mathematics

2 answers:

Viefleur [7K]2 years ago

6 0

Answer:

B) x = 3 or x = -5/2

Step-by-step explanation:

Solve for x over the real numbers:

2 x^2 - x = 15

Subtract 15 from both sides:

2 x^2 - x - 15 = 0

x = (1 ± sqrt((-1)^2 - 4×2 (-15)))/(2×2) = (1 ± sqrt(1 + 120))/4 = (1 ± sqrt(121))/4:

x = (1 + sqrt(121))/4 or x = (1 - sqrt(121))/4

sqrt(121) = sqrt(11^2) = 11:

x = (1 + 11)/4 or x = (1 - 11)/4

(1 + 11)/4 = 12/4 = 3:

x = 3 or x = (1 - 11)/4

(1 - 11)/4 = -10/4 = -5/2:

Answer: x = 3 or x = -5/2

Tasya [4]2 years ago

5 0

The answer is b have a great day also could I get brainliest

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