Use the quadratic formula to solve for x 8x^2+7x+1=0 plz help

Mathematics

2 answers:

vagabundo [1.1K]2 years ago

4 0

Answer:

X= -7 ± √17 / 16

x= - 0.7798...

Step-by-step explanation:

Katarina [22]2 years ago

3 0

Step-by-step explanation:

$8x {}^{2} + 7x + 1 = 0 \\ d = 49 - 32 = 1 \\ x1 = \frac{ - 7 - \sqrt{17} }{16} \\ x2 = \frac{ - 7 + \sqrt{17} }{16}$

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Cynthia Besch wants to buy a rug for a room that is 24 ft wide and 33 ft long. She

qaws [65]

<h3>Answer: 16 ft by 25 ft</h3>

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Explanation:

Refer to the diagram below.

The outer dimensions 24 ft and 33 ft shrink down to 24-2x ft and 33-2x ft respectively. This subtraction of 2x is due to subtracting two copies of x per side.

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Plug in a = 4, b = -114, c = 392

$x = \frac{-b\pm\sqrt{b^2-4ac}}{2a}\\\\x = \frac{-(-114)\pm\sqrt{(-114)^2-4(4)(392)}}{2(4)}\\\\x = \frac{114\pm\sqrt{6724}}{8}\\\\x = \frac{114\pm82}{8}\\\\x = \frac{114+82}{8} \ \text{ or } \ x = \frac{114-82}{8}\\\\x = \frac{196}{8} \ \text{ or } \ x = \frac{32}{8}\\\\x = 24.5 \ \text{ or } \ x = 4\\\\$