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3 years ago

The value of y varies directly with x. If x = 4, then y = 32. What is the value of x when y = 128?

Mathematics

1 answer:

pashok25 [27]3 years ago

6 0

Answer:

32/4= 8 (there is a factor of 8 between x and y at all times)

128/8 = 16 (divide y by 8 to find out what x is.

x= 16 when y= 128

Step-by-step explanation:

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Which angles pair represents alternate interior angles

aliya0001 [1]

Answer:

C) 4 and 5

Step-by-step explanation:

Alternate interior angles are:

Alternate

Opposite sides of the transversal line(line that goes through other lines)

Interior

Inside of the two lines the transversal is going through

4 and 5 are angles are on either side of the transversal line

And they are inside two lines

If my answer is incorrect, pls correct me!

If you like my answer and explanation, mark me as brainliest!

-Chetan K

6 0

3 years ago

Consider the equation below. (If an answer does not exist, enter DNE.) f(x) = x3 − 6x2 − 15x + 2 (a) Find the interval on which

Burka [1]

Answer:

a) $(-\infty, -1) \cup (5, \infty)$

b) $(-1,5)$

Step-by-step explanation:

The first step to solve this question is finding the roots of the derivative of x.

Solving a quadratic equation:

Given a second order polynomial expressed by the following equation:

$ax^{2} + bx + c, a\neq0$ .

This polynomial has roots $x_{1}, x_{2}$ such that $ax^{2} + bx + c = a(x - x_{1})*(x - x_{2})$ , given by the following formulas:

$x_{1} = \frac{-b + \sqrt{\bigtriangleup}}{2*a}$

$x_{2} = \frac{-b - \sqrt{\bigtriangleup}}{2*a}$

$\bigtriangleup = b^{2} - 4ac$

In this question:

$f(x) = x^{3} - 6x^{2} - 15x + 2$

$f'(x) = 3x^{2} - 12x - 15$

Finding the roots:

$3x^{2} - 12x - 15 = 0$

Simplifying by -3

$x^{2} - 4x - 5 = 0$

So $a = 1, b = -4, c = -5$

Then

$\bigtriangleup = (-4)^{2} - 4*1*(-5) = 36$

$x_{1} = \frac{-(-4) + \sqrt{36}}{2} = 5$

$x_{2} = \frac{-(-4) - \sqrt{36}}{2} = -1$

So the function can be divided in three intervals.

They are:

Less than -1

Between -1 and 5

Higher than 5

In which it increases and which it decreases?

Less than -1

Lets find the derivative in a point in this interval, for example, -2

$f'(x) = 3x^{2} - 12x - 15$

$f'(-2) = 3*(-2)^{2} - 12*(-2) - 15 = 21$

Positive.

So in the interval of $(-\infty, -1)$ , the function increases.

Between -1 and 5

Will choose 0.

$f'(x) = 3x^{2} - 12x - 15$

$f'(0) = 3*(0)^{2} - 12*(0) - 15 = -15$

Negative.

So in the interval of $(-1,5)$ , the function decreases.

Higher than 5

Will choose 6.

$f'(x) = 3x^{2} - 12x - 15$

$f'(6) = 3*(6)^{2} - 12*(6) - 15 = 21$

Positive

So in the interval of $(5, \infty)$ , the function increases.

(a) Find the interval on which f is increasing.

Using interval notation

$(-\infty, -1) \cup (5, \infty)$

b) Find the interval on which f is decreasing.

$(-1,5)$

5 0

3 years ago

A bag contains 6 red marbles, 6 white marbles, and 4 blue marbles. Find P(red or blue).

maks197457 [2]

Answer:

I think its B. because if you put 6/4and reduce it it would be 3/2

Step-by-step explanation:

5 0

3 years ago

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Which shows another way to write 95?

AveGali [126]

Nine to the fifth power is nine multiplied by nine five times so D. is the answer.

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3 years ago

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Solve 2(x + 1) + 4 = 8.

Dennis_Churaev [7]

2X+2+4=8
2X+6=8
-6 -6
_________
2X=2
_____
2 2
X=1

3 0

3 years ago

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