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3 years ago

Solve each equation. Showing your reasoning. X^2-6x-20=7

Mathematics

1 answer:

scoundrel [369]3 years ago

4 0

Answer:

x=-3,x=9

Step-by-step explanation:

x^2-6x-20-7=0

x^2-6x-27=0

x^2-(9-3)x-27=0

x^2-9x+3x-27=0

x(x-9)+3(x-9)=0

(x+3)(x-9)=0

x=-3,x=9

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3⁄2 c + 23 = 38<br><br> can you help me find out what c is pretty please

kolbaska11 [484]

Answer:

C=10

Step-by-step explanation:

To solve this problem, first, you have to isolate it on one side of the equation. Remember, isolate c on one side of the equation.

3/2c+23-23=38-23 (subtract 23 from both sides.)

38-23 (solve.)

38-23=15

3/2c=15

2*3/2c=15*2 (multiply 2 from both sides.)

15*2 (solve.)

15*2=30

3c=30

3c/3=30/3 (divide by 3 from both sides.)

30/3 (solve.)

30/3=10

c=10

6 0

3 years ago

Prac

PtichkaEL [24]

Answer:

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3 years ago

A multiple choice test has four possible answers for each question. Let X be the number of correct responses in a test of 100 qu

dimulka [17.4K]

Answer:

a. 4.33.

Step-by-step explanation:

If there is only one correct answer out of four alternatives, the expected proportion of correct answers is p =0.25

Sample size (n) = 100 questions

The standard deviation of a proportion 'p' is given by:

$s=\sqrt{\frac{p*(1-p)}{n} }$

Applying the given data:

$s=\sqrt{\frac{0.25*(1-0.25)}{100}}\\s=0.0433$

If X is the number of correct responses in 100 guesses, the standard deviation of X is:

$\sigma = n*s=100*0.0433\\\sigma = 4.33$

The standard deviation of X is 4.33 questions.

7 0

3 years ago

Evaluate the expression for the given value of the variable.<br><br> |4b-8|+|-1-b^2|+2b^3;b=2

Elena-2011 [213]

In this question we already know the value of 'b' so put the value b=2 in the equation

=|4(2)-8| + |-1-(2)^2| + 2(2)^3

=|8-8| + |-1-4| + 2(8)

=0 -5 +16

=11

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3 years ago

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Vedmedyk [2.9K]

Answer:

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Solution given:

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4Tan² $\theta$ -3Tan² $\theta$ +4Cot² $\theta$ -3Cot² $\theta$

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7 0

2 years ago