Math Help now !!!! Plz
posted by David .
Solve using the quadratic formula
X^24x=21

Learn the quadratic formula:
x = [b +/sqrt(b^2 4ac)]/2a
In your case a = 1, b = 4 and c = 21
x = [4 +/sqrt(100)]/2
You finish it. You surely know what the square root of 100 is.
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