8,12,16 find the 31st term

Lady_Fox [76]

$a)\\\\x^2-2x-4=0\\\\x^2-2x=4\\\\x^2-2x+1^2=4+1^2\\\\(x-1)^2=5\\\\x-1=\pm\sqrt5\\\\\underline{x=\pm\sqrt5+1\approx-1.24\ or\ 3.24}\\\\\\b)\\\\x^2-4x-2=0\\\\x^2-4x=2\\\\x^2-4x+2^2=2+2^2\\\\(x-2)^2=6\\\\x-2=\pm\sqrt6\\\\\underline{x=\pm\sqrt6+2\approx-0.45\ or\ 4.45}$

$c)\\\\x^2+8x+5=0\\\\x^2+8x=-5\\\\x^2+8x+4^2=-5+4^2\\\\(x+4)^2=11\\\\ x+4=\pm\sqrt{11}\\\\\underline{x=\pm\sqrt{11}-4\approx-7.32\ or\ -0.68}\\\\\\x)\\\\x^2+22x-15=0\\\\x^2+22x=15\\\\x^2+22x+11^2=15+11^2\\\\(x+11)^2=136\\\\x+11=\pm\sqrt{136}\\\\\underline{x=\pm\sqrt{136}-11\approx-22.66\ or\ 0.66}$

$e)\\\\x^2-7x+10=0\\\\x^2-7x=-10\\\\x^2-7x+(\frac72)^2=-10+(\frac72)^2\\\\x^2-7x+(\frac72)^2=-10+(\frac72)^2\\\\(x-\frac72)^2=-\frac{20}4+\frac{49}4\\\\ (x-\frac72)^2=\frac{29}4\\\\x-\frac72=\pm\sqrt{\frac{29}4}\\\\ \underline{x=\pm\frac{\sqrt{29}}2+\frac72\approx6.19\ or\ 0.81}\\\\\\f)\\\\x^2+5x-2=0\\\\x^2+5x=2\\\\x^2+5x+(\frac52)^2=2+(\frac52)^2\\\\(x+\frac52)^2=2+6.25 \\\\x+\frac52=\pm\sqrt{8.25}\\\\\underline{x=\pm\sqrt{8.25}-\frac52\approx-5.37\ or\ 0.37}$

$g)\\\\x^2+9x-4=0\\\\x^2+9x=4\\\\x^2+9x+(\frac92)^2=4+(\frac92)^2\\\\(x+\frac92)^2=4+20.25\\\\x+\frac92=\pm\sqrt{24.25}\\\\\underline{x=\pm\sqrt{24.25}-4.5\approx-9.42\ or\ 0.52}$

$h)\\\\x^2-3x-6=0\\\\x^2-3x=6\\\\x^2-3x+(\frac32)^2=6+(\frac32)^2\\\\(x-\frac32)&^2=6+2.25\\\\x-\frac32=\pm\sqrt{8.25}\\\\ \underline{x=\pm\sqrt{8.25}+1.5\approx4.37\ or-1.37}$

3 0

3 years ago

Assume that the GMAT scores across the U.S. follow a bell shaped distribution (symmetric and unimodal) with mean 549 and standar

blondinia [14]

Answer:

The GMAT score corresponding to the 16th percentile is 473.

Step-by-step explanation:

Empirical Rule.

The Empirical Rule states that, for a normally distributed random variable:

Approximately 68% of the measures are within 1 standard deviation of the mean.

Approximately 95% of the measures are within 2 standard deviations of the mean.

Approximately 99.7% of the measures are within 3 standard deviations of the mean.

68% of the measures within 1 standard deviation of the mean.

This means that they are between the 50 - (68/2) = 50 - 34 = 16th percentile(one standard deviation below the mean) and the 50 + (68/2) = 50 + 34 = 84th percentile(one standard deviation above the mean).

In this question:

Mean of 549, standard deviation of 76.

16th percentile:

One standard deviation below the mean, so 549 - 76 = 473.

The GMAT score corresponding to the 16th percentile is 473.

5 0

3 years ago

Suppose johnny invests 2745 into an account which has been earning intrest for many years and how he now has a total of 39974. I

Basile [38]

See the attachment..............

4 0

4 years ago

PLEASE HELP ME

german

Step-by-step explanation:

Case 1.

|x|>5

⇔-x>5 and x>5

so it is not possible.

Case 2.

|x|<5

⇔x<5 and -x<5

⇔x<5 and x>-5

⇔-5<x<5

3 0

4 years ago

2. What is the center and radius of the circle given by the equation x^2+(y−11)^2=144?

juin [17]

Answer: Center: (0,0)

Radius:12

4 0

4 years ago