All categories

3 years ago

Can someone help me please!!

Mathematics

2 answers:

Lynna [10]3 years ago

8 0

Answer:

b because the value are correct

Step-by-step explanation:

Vladimir [108]3 years ago

4 0

Answer:

Yes I can. So I will.

Step-by-step explanation:

Anytime you found yourself in doubt and danger about equations, you can use Geogebra Graph Calc - search for it -, and he will show you the graphic.

But, as I know that you are one the LAST HEROES IN EARTH, I pretty sure you don't want to just surrender yourself for a computer machine.

Let's calculate it:

4x² - 39x + 77

Bháskara Formula, you probably know her as Resolutive Formula, as she is known in my country, is:

$BF=\frac{-b \sqrt[]{b^2 - 4ac} }{2a}$ there is also two signals + - betwen -b and the root.

She's one of the best ways to find roots for quadratic equations.

We will need to do that to find the interval required.

Also, remember that a generic quadratic equation can be describe as:

ax² + bx + c

So, knowing that in this equation

a = 4 / b = -39 / c = 77

We can proceed.

x' = - (-39) + $\sqrt[]{(-39)^2 - 4.4.77}$ / 2.4

x' = 39 + 17/ 8

x' = 7

x'' = 39 -17/8

x'' = 2,75

Now, you should know that when A > 0 the quadratic equation has her concavity facing down.

As we have the values of the roots, 7 and 2,75, we know that betwen them the equation has negative values.

That also means that all values higher than 7 and lower than 2,75 give to us a positive value.

Final answer:

x<2,75 and x>7

You will see in annex the graphic.

You might be interested in

Can someone tell me if im right? PLEASE DONT JUST SAY YES if you don’t know

tia_tia [17]

Answer: You are incorrect, the slope is correct, but the actual y-intercept is 205 ft.

Then the equation is:

y = (-15 ft/min)*x + 205 ft

Step-by-step explanation:

Ok, let's solve this.

We know that water is drained from a reservoir, let's assume that we can model this situation with a linear relation:

y = a*x + b

Where x is time, y is the height of the water in the reservoir, a is the slope (in this case represents how much changes the height of the water in the reservoir in one unit of time) and b is the initial height of the water in the reservoir.

We know that for a line that passes through the points (x₁, y₁) and (x₂, y₂) the slope is:

a = (y₂ - y₁)/(x₂ - x₁)

For this particular case we know that after 2 minutes the height of the water is 175 ft, then we have the point (2 min, 175 ft)

and after 5 minutes (so 7 minutes in total), the height of the water is 100ft, then: (7 ft, 100ft)

Then the slope of this:

a = (100 ft - 175 ft)/(7 min - 2 min) = (-75ft/5min) = - 15 ft/min

Then our line is something like:

y = (-15ft/min)*x + b

To find the value of b, we can use the fact that when x = 2 min, y = 175 ft

So if we replace these two values in the equation we get:

175ft = (-15 ft/min)*2 min + b

175 ft = -30 ft + b

175 ft + 30 ft = b

(here is your problem, it seems like you subtracted instead of adding in this part)

205 ft = b

Then the equation is:

y = (-15 ft/min)*x + 205 ft

So you are incorrect (but only for a little bit), you computed wrong the y-intercept.

3 0

3 years ago

27. Stuart wants to play a trick on his friend by hiding his pencil in the box of tissues shown below. If

Alex17521 [72]

Answer:

Well if it’s a regular box I’m sure it will fit, because a box of tissues is at least 10 inches long in diameter.

5 0

4 years ago

How do you write this in standard notation 6x10 to the power of 3

Olin [163]

The way to write this would be 6000

7 0

3 years ago

The components of vector A are (10.5, 10.2). Waht is the magnitude of the vector?

Nataly_w [17]

Answer:

$||\overrightarrow{v}||\approx14.64$

Step-by-step explanation:

The magnitude of a vector $\displaystyle \overrightarrow{v}=\langle x,y\rangle$ is $||\overrightarrow{v}||=\sqrt{x^2+y^2}$ , which essentially describes the length of the vector itself between the initial and terminal points:

$||\overrightarrow{v}||=\sqrt{x^2+y^2}\\\\||\overrightarrow{v}||=\sqrt{(10.5)^2+(10.2)^2}\\\\||\overrightarrow{v}||=\sqrt{110.25+104.04}\\\\||\overrightarrow{v}||=\sqrt{214.29}\\\\||\overrightarrow{v}||\approx14.64$

6 0

2 years ago

Simplify the expression 4.2 - 5 -6.5w

WARRIOR [948]

Answer:

−6.5w−0.8

Step-by-step explanation:

4.2+−5+−6.5w

Combine Like Terms:

=4.2+−5+−6.5w

=(−6.5w)+(4.2+−5)

=−6.5w+−0.8

Brainless please

5 0

3 years ago

Can someone help me please!!​

Can someone help me please!!