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3 years ago

Please help me with this

Mathematics

1 answer:

goldfiish [28.3K]3 years ago

3 0

$3z^{2} -10z-5$

Insert the value of z into the equation

$3(4)^{2} -10(4)-5$

$3(16) -40-5$

$48-40-5$

$3$

The value of the expression $3z^{2} -10z-5$ when $z=4$ is 3

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Wing figures, solve for x. Complete parts (a) 80° 53

Korolek [52]

Answer:

x = 25°

Step-by-step explanation:

Applying,

Sum of the angle in the triangle = 180°

From the diagram,

First angle of the triangle = 55° (vertically opposite angles are equal)

Second angle of the traingle = 180-80 = 100° (sum of the angle in a straight line)

Third angle of the triangle = x

Therefore,

x+55+100 = 180

x+155 = 180

x = 180-155

x = 25°

7 0

3 years ago

Find the missing measure for a right circular cone given the following information. Find L.A. if r = 6 and h = 8 48 60 96

svetlana [45]

$\bf \textit{lateral area of a cone}\\\\
LA=\pi r\sqrt{r^2+h^2}\quad 
\begin{cases}
r=radius\\
h=height\\
-----\\
r=6\\
h=8
\end{cases}\implies LA=\pi(6)\sqrt{6^2+8^2}
\\\\\\
LA=6\pi \sqrt{100}\implies LA=6\pi (10)\implies LA=60\pi$

8 0

4 years ago

POSSIBLE POINTS: 2

serious [3.7K]

Answer: max capacity is 1625 gallons.

Diagram is shown below.

=========================================================

Explanation:

We'll draw two horizontal number lines to help make a comparison or connection between percentages and tank capacity.

For the top number line, make 5 sections with the labels: 0%, 20%, 40%, 60%, 100%. The reason I'm picking 5 is because 40% = 40/100 = 2/5. So having 40% capacity means we're 2/5 full. That denominator 5 tells us how to subdivide each number line.

The bottom number line will also have 5 sections. We only know one label for this bottom portion right now. That label is 650. Place this directly under the "40%". This visually is one way to represent that 650 gallons is 40% filled. See the diagram below.

Cut the 650 in half to get 325. This corresponds to 40% cut in half to get 20%. Therefore, 325 will go under the 20%. Being 20% full means we have 325 gallons of water.

To figure out the 60% portion, we will multiply 325 by 3. This is because 3*20% = 60%, so 3*325 = 975. We'll write "975 gallons" under the "60%"

Then we have 1300 gallons under the 80% since 4*325 = 1300. Note how 4*20% = 80%, so that's where the '4' multiplier comes from.

Finally, we multiply 325 by 5 to get 1625 and that represents the full tank's capacity. Technically we could have just jumped to this directly without having to find the 60% or 80% capacity values, but it's good practice I think.

Again the diagram is shown below. The answer we're after is at the very bottom right corner. It's under the 100% to indicate the tank is completely full, or has reached max capacity.

-----------------------

Here's a way to find the answer without a double number line. This method involves setting up a proportion.

(40% full)/(650 gallons) = (100% full)/(x gallons)

40/650 = 100/x

40x = 650*100

40x = 65000

x = 65000/40

x = 1625

We confirm that the tank's max capacity is 1625 gallons.

4 0

3 years ago

The graph shows the solution to which system of equations?

Sedaia [141]

So let's start by guesstimating the slopes:
the green line has a slope close to -x, but more negative than that, possibly -2; the pink line has a slope close to +x, but higher towards +2.

Next let's look at the solution: the two lines intersect at the point (1, -1).
**you could just simple plug that x (1) into all the equations, but let's rule out answers anyway. ;)

A) is incorrect because the slopes of -1 and +1 are off from out predicted -2 and +2
B) is incorrect because of a similar reason, the slopes of +3 and +1 don't make any sense
C) Ooh, we do have a +2 and -2 for the slopes, and... violà! plug in 1 for the x's and we get -1 for the y in both equations
D) slopes are closer than in A and B, but plugging in 1 doesn't get us -1

So the correct answer is:
C) y = 2x - 3 and y = −2x + 1

6 0

4 years ago

Write the equation of the line in fully simplified slope-intercept form.

fiasKO [112]

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