Question

simplify using the Identify (x+3) (x+7)​

Answer 1

Identity to be used: (x+a)(x+b) = x²+(a+b)x+ab

= x²+(3+7)x+(3×7) = x²+10x+21

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Answer 2

Step-by-step explanation:

=

${x}^{2} + 7x \: + 3x + 21$

=

$x(x + 7) \: + 3(x + 7)$

=

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

=Now

$x = - 7 \\ = - 3$

Answer