Algebra

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Use the quadratic formula to solve the equation. Give exact answers.

2x^2 + 11x - 21 = 0

a) -3/2, 7
b) 3/2, -7
c) 3/2, 7
d) -3/2, -7

I could not get any of these answers.

  • Algebra -

    The answer is (b), x1=3/2, x2=-7
    Check that you use the formula
    x=(-b+/-sqrt(B2-4ac))/(2a)

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