Question 371342
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Hi,
solve by factoring and using the principle of zero products
x^2+4x-21=0
factoring
(x+7)(x-3) = 0  Note: the SUM of the outer product,-3x and inner product,7x = 4x
using the principle of zero products
(x+7= 0
x = -7
(x-3) = 0
x = 3