All categories

3 years ago

Given: h(x) = x2 – 8x Find: h(-4)

Mathematics

2 answers:

Maslowich3 years ago

6 0

Answer:48

Step-by-step explanation:

tekilochka [14]3 years ago

6 0

(-4)^2-8(-4)
16+32
46
The answer is 46

You might be interested in

In a sale normal prices are reduced by 10%

astraxan [27]

in sale normal prices are reduced by 10% nathaile bought a pair of shoes in the sale for $54 10% of 54 is 59.4

5 0

3 years ago

Read 2 more answers

If it took 8 people 10 hours to build a barn, how long would it take 14 people to build the same barn?

Basile [38]

Answer:

if 8 people take 10 hours then

1 people 10 / 8 = 1.25 hours

then 14 people =

14 * 1.25 = 17.5 hours

8 0

2 years ago

Determine the number of ways she can arrange her daily schedule.

natita [175]

Answer:

This can be found by using the permutations and combinations formuals.

Combinations being the C equation and Permutations being the P equation.

$P(n,r)=\frac{6!}{(6-6)!}=720$

Explanation:

A permutation is used for the list of data (where the order of the data matters) and the combination is used for a group of data (where the order of data doesn't matter).

3 0

2 years ago

Find the value of B - A if the graph of Ax + By = 3 passes through the point (-7, 2), and is parallel to the graph x + 3y = -5.

Elena-2011 [213]

Answer:

$B - A = -6$

Step-by-step explanation:

Given

Point: (-7,2)

x + 3y = -5

Required

Find B- - A in Ax + By = 3

To start with; we need to calculate the slope of x + 3y = -5

$x + 3y = -5$

Subtract x from both sides

$x - x + 3y = -5 - x$

$3y = -5 - x$

Divide both sides by 3

$\frac{3y}{3} = -\frac{5}{3} - \frac{x}{3}$

$y = -\frac{5}{3} - \frac{x}{3}$

The slope of the line is the coefficient of x

Slope = $- \frac{1}{3}$

The question says line Ax + By = 3 is parallel to line x + 3y = -5; This means that they have the same slope of $- \frac{1}{3}$

Having calculated the slope, next is to calculate the equation of the line using the following formula;

$m = \frac{y - y_1}{x - x_1}$

Where m is the slope; m = $- \frac{1}{3}$ ; $(x_1, y_1) = (-7,2)$

Substitute these values in the formula above; the formula becomes

$-\frac{1}{3} = \frac{y - 2}{x - -7}$

$-\frac{1}{3} = \frac{y - 2}{x +7}$

Cross Multiply

$-1(x+7) = 3(y-2)$

Open brackets

$-x - 7 = 3y - 6$

Add x to both sides

$x - x - 7 = 3y - 6 + x$

$-7 = 3y - 6 +x$

Add 6 to both sides

$-7 + 6 = 3y -6 + 6 + x$

$-1 = 3y + x$

Multipby both sides by -3

$-3(-1) = -3(3y + x)$

$3 = -9y - 3x$

$-9y - 3x = 3$

$-3x - 9y = 3$

Comparing the above to Ax + By = 3

$Ax = -3x\\A = -3$

$By = -9y\\B = -9$

$B - A = -9 - (-3)$

$B - A = -9 + 3$

$B - A = -6$

3 0

3 years ago

Genius question: A long level railway bridge passes over a railroad track, which is 100 feet below it and at right angles to it.

nataly862011 [7]

Answer: <u>110 feet per second</u>

Step-by-step explanation:

In this problem we will assume that the car at 45 miles per hour is moving into the x direction with a high of 100 feet, and the train is going in the y direction, so they trajectories will made an angle of 90º.

Now we can calculate the speed of the trains in feet per second so:

$S1=\frac{45*5280}{3600}=66$

$S2=\frac{60*5280}{3600}=88$

So we can make a right triangle with sides 66 and 88 and the hypotenuse will be the rate that the trains will separate per second so:

$h=\sqrt{66^{2} +88^{2} } =\sqrt{4356+7744}$

$h=\sqrt{12100}=110$

Is important to have in mind that the initial high is not going to change how fast the trains will separate, however, if we are going to calculate the distance we should have it in the calculations.

7 0

3 years ago