Question

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$(x + 3)(x + 4)$
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Answer 1

Answer:

x(x+4) + 3(x+4)

x^2 + 4x + 3x + 12

${x }^{2} + 7x + 12$

Answer 2

Answer:

$(x + a) \:( x + b) = {x}^{2} + (a + b)x + ab \\( x + 3) \: (x + 4) = {x}^{2} + (3 + 4)x + 3 \times 4 \\ {x}^{2} + 7x + 12$