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3 years ago

5

Simplify (7x-1)(2x+5)

2 answers:

Sergio039 [100]3 years ago

6 0

$\text{Simplify by using FOIL}\\\\\text{(First, Outside, Inside, Last}\\\\\text{Solve:}\\\\(7x-1)(2x+5)\\\\(7x)(2x)+(7x)(5)+(-1)(2x)+(-1)(5)\\\\14x^2+35x-2x-5\\\\\text{Combine like terms}\\\\\boxed{14x^2+33x-5}$

Alex73 [517]3 years ago

5 0

Step-by-step explanation:

$(7x-1)(2x+5) = 0 \\ 14x {}^{2} + 35x - 2x - 5 = 0 \\ 14x {}^{2} + 33x - 5 = 0 \\$

now,

$14 {x}^{2} - 2x + 35x - 5 = 0 \\ 2x(7x - 1) + 5(7x - 1) = 0 \\ (2x + 5)(7x - 1) = 0 \\ 2x + 5 = 0 \: \: \: \: or \: \: \: \: \: 7x - 1 = 0 \\ \\ x = - \frac{5}{2} \: \: \: \: or \: \: \: \: x = \frac{1}{7}$

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Step-by-step explanation:

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