Solve the equation x^2-4x-21=0

x = 7 and x = -3

Step-by-step explanation:

x^2-4x-21=0

you can factor to get

(x-7)(x+3)=0

then set each equal to 0

x - 7 = 0 and x + 3 = 0

then just solve for x!

x = 7 and x = -3

step-by-step explanation:

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