Follow the process of completing the square to solve 2x2 + 8x - 12 = 0.

1 answer:

8 0

Please: Use "^" to denote exponentiation: 2x^2 + 8x - 12 = 0

Reduce this by div. every term by 2: x^2 + 4x - 6 = 0

Here a=1, b=4 and c = -6. Square half of b, obtaining (4/2)^2 = 4, and add, and then subtract, this 4 to x^2 + 4x - 6:

 x^2 + 4x +4 - 4 - 6 = 0. Rewrite the square as (x+2)^2, obtaining new equation

(x+2)^2 = 10. Take the sqrt of both sides: x+2 = plus or minus sqrt(10).

Finally, solve for x: x = -2 plus or minus sqrt(10).

You might be interested in

Miss lead says that if y varies directly with x and y=15 when x=-3, then y=-20 when x=4. Is she correct? Answer in complete sent

gizmo_the_mogwai [7]

Answer:

Yes, she is correct.

Step-by-step explanation:

y = kx is direct variation

15 = k*-3

k = -5.

So the equation of variation is

y = -5x

When x = -4:

y -5*-4 = 20.

6 0

2 years ago

M-6=10 What does m equal?

Sliva [168]

M is 6 more than 10 so it will be 16

8 0

3 years ago

Read 2 more answers

<img src="https://tex.z-dn.net/?f=the%20%5C%3A%20angle%20%5C%3A%20of%20%5C%3A%20measure%20%5C%3A%20%20%5Cfrac%7B31%5Cpi%7D%7B6%7

Yakvenalex [24]

Answer:

3rd quadrant

Step-by-step explanation:

First we just convert the angle from radians to degrees
$\frac{31\pi radians }{6}*\frac{180degrees}{\pi radians} =\frac{31*180}{6} degrees=930degrees$
Now that's too big, all this means is if we start rotating from the positive y-axis in a circle we will cross the starting point 2 times, 2 full circles;
$930degrees-360degrees=570degrees\\570degrees-360degrees=210degrees$
Now in which quadrant it 210 degrees?
0 degrees to 90 degrees is 1st quadrant
90 degrees to 180 degrees is 2nd quadrant
180 degrees to 270 degrees is 3rd quadrant
270 degrees to 360 degrees is 4th quadrant
So our answer is the 3rd quadrant.