Posted by **carolyn** on Monday, January 3, 2011 at 9:10pm.

Solve the equation x2 + 8x – 2 = 0 using both

a. The quadratic formula

b. Completing the square

Write a paragraph or two comparing and contrasting the two methods. Explain which method you prefer and why.

c) Use the accompanying graph to estimate the time at

which the workers are most efficient.

d) Use the accompanying graph to estimate the

maximum number of components assembled per

hour during an 8-hour shift.

- algebra -
**Reiny**, Monday, January 3, 2011 at 9:26pm
formula:

x = (-8 ± √72)/2

= (-8 ± 6√2)/2 = -4 ± 3√2

completing the square

x^2 + 8x = 2

x^2 + 8x + **16** = 2 + **16**

(x+4)^2 = 18

x+4 = ± √18 = ±3√2

x = -4 ± 3√2

notice that completing the square gives you the reduced answer.

(If the equation starts with 1x^2 and the x term is even, I always use completing the square instead of the formula)

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