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3 years ago

Solve 2x - 9 - 7x = 11. A. -4 B. -1/4 C.2/5 D. 4

Mathematics

2 answers:

zalisa [80]3 years ago

7 0

2x-9-7x=11
(add common terms together)
-5x-9=11
(get x alone and positive on one side of the equation)
5x=-20
x=-4

HACTEHA [7]3 years ago

4 0

A. -4

-5x divided by 20 = -4

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What is the estimate of forgive 6in by 4in

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The diameter is, half of that would be the radius, which is 3.

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3 years ago

The scores for a certain test of intelligence are normally distributed with mean 85 and standard deviation 11. Find the 90th per

jonny [76]

Answer:

99.1 is the 90th percentile of these scores.

Step-by-step explanation:

We are given the following information in the question:

Mean, μ = 85

Standard Deviation, σ = 11

We are given that the distribution of score is a bell shaped distribution that is a normal distribution.

Formula:

$z_{score} = \displaystyle\frac{x-\mu}{\sigma}$

We have to find the value of x such that the probability is 0.90

$P( X < x) = P( z < \displaystyle\frac{x - 85}{11})=0.90$

Calculation the value from standard normal z table, we have,

$P(z \leq 1.282) = 0.90$

Putting values, we get,

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3 years ago

If you place a 17-foot ladder against the top of a 8-foot building, how many feet will the bottom of the ladder be from the bott

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Answer:

15 feet

Step-by-step explanation:

This problem involves using the Pythagorean theorem, since the figure made with the ladder, building, and ground would make a right triangle. You are given the values 17ft and 8ft, which is enough to plug into the Pythagorean theorem.

The ladder, 17ft, would be the longest side (hypotenuse). The 8ft building would be one of the legs of the right triangle.

1. Plug your given values correctly into the Pythagorean Theorem.

$a^{2} + b^{2} = c^{2}$

$8^{2} + b^{2} = 17^{2}$

2. Now solve for b, which is your unknown distance (the distance the bottom of the ladder is from the bottom of the building).

$8^{2} + b^{2} = 17^{2}$ --> Square 8 and 17

$64 + b^{2} = 289$ --> Subtract 64 from both sides

$b^{2} = 225$ --> Square root both sides to get b by itself

b = 15

3. The distance is 15 feet

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2 years ago

You have a jar of Marbles in front of you 2 are Cordovan, 9 are yellow, 3 are white and 7 are red. What is the probability, as a

liubo4ka [24]

Answer:

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Step-by-step explanation:

Assuming that this is without replacement,

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