Ishaan knows that 3 solves x² + kx - 21 = 0. What number is k? | StemPy Lab

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Ishaan knows that 3 solves x² + kx - 21 = 0. What number is k? | StemPy Lab

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Ishaan knows that 3 solves x² + kx - 21 = 0. What number is k?

MathematicsMediumHigh School (9–10)GeneralAlgebra › Quadratic Equations

Created by StemPy Lab

Ishaan knows that $3$ solves $x^2 + kx - 21 = 0$ . What number is $k$ ?

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