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3 years ago

Please can help me ?

Mathematics

1 answer:

valentinak56 [21]3 years ago

7 0

Answer:

??????????????

Step-by-step explanation:

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A machine covers 5/8 square foot in 1/4 hour. what is the unit rate?

Ilia_Sergeevich [38]

we know that

<u>Unit Rate</u> is the ratio of two measurements in which the second term is one

to find the unit rate divide $(5/8)$ by $(1/4)$

$Unit\ rate=\frac{(5/8)}{(1/4)}= \frac{5}{8}*4= \frac{2.5}{1} =2.5 \frac{ft^{2}}{hour}$

therefore

<u>the answer is</u>

The unit rate is $2.5 \frac{ft^{2}}{hour}$

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3 years ago

Which two are equivalent?

never [62]

Answer:

Expression I and IV

Step-by-step explanation:

Expression I simplified :

3n + 7 + n + 4n
8n + 7
Expression I = Expression IV

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2 years ago

Find the volume and area for the objects shown and answer Question

klio [65]

Step-by-step explanation:

You must write formulas regarding the volume and surface area of the given solids.

$\bold{\#1\ Rectangular\ prism:}\\\\V=lwh\\SA=2lw+2lh+2wh=2(lw+lh+wh)\\\\\bold{\#2\ Cylinder:}\\\\V=\pi r^2h\\SA=2\pi r^2+2\pi rh=2\pir(r+h)\\\\\bold{\#3\ Sphere:}\\\\V=\dfrac{4}{3}\pi r^3\\SA=4\pi r^2$

$\bold{\#4\ Cone:}\\\\V=\dfrac{1}{3}\pi r^2h\\\\\text{we need calculate the length of a slant length}\ l\\\text{use the Pythagorean theorem:}\\\\l^2=r^2+h^2\to l=\sqrt{r^2+h^2}\\\\SA=\pi r^2+\pi rl=\pi r^2+\pi r\sqrt{r^2+h^2}=\pi r(r+\sqrt{r^2+h^2})\\\\\bold{\#5\ Rectangular\ Pyramid:}\\\\V=\dfrac{1}{3}lwh\\\\$

$\\\text{we need to calculate the height of two different side walls}\ h_1\ \text{and}\ h_2\\\text{use the Pythagorean theorem:}\\\\h_1^2=\left(\dfrac{l}{2}\right)^2+h^2\to h_1=\sqrt{\left(\dfrac{l}{2}\right)^2+h^2}=\sqrt{\dfrac{l^2}{4}+h^2}=\sqrt{\dfrac{l^2}{4}+\dfrac{4h^2}{4}}\\\\h_1=\sqrt{\dfrac{l^2+4h^2}{4}}=\dfrac{\sqrt{l^2+4h^2}}{\sqrt4}=\dfrac{\sqrt{l^2+4h^2}}{2}$

$\\\\h_2^2=\left(\dfrac{w}{2}\right)^2+h^2\to h_2=\sqrt{\left(\dfrac{w}{2}\right)^2+h^2}=\sqrt{\dfrac{w^2}{4}+h^2}=\sqrt{\dfrac{w^2}{4}+\dfrac{4h^2}{4}}\\\\h_2=\sqrt{\dfrac{w^2+4h^2}{4}}=\dfrac{\sqrt{w^2+4h^2}}{\sqrt4}=\dfrac{\sqrt{w^2+4h^2}}{2}$

$SA=lw+2\cdot\dfrac{lh_1}{2}+2\cdot\dfrac{wh_2}{2}\\\\SA=lw+2\!\!\!\!\diagup\cdot\dfrac{l\cdot\frac{\sqrt{l^2+4h^2}}{2}}{2\!\!\!\!\diagup}+2\!\!\!\!\diagup\cdot\dfrac{w\cdot\frac{\sqrt{w^2+4h^2}}{2}}{2\!\!\!\!\diagup}\\\\SA=lw+\dfrac{l\sqrt{l^2+4h^2}}{2}+\dfrac{w\sqrt{w^2+4h^2}}{2}\\\\SA=\dfrac{2lw}{2}+\dfrac{l\sqrt{l^2+4h^2}}{2}+\dfrac{w\sqrt{w^2+4h^2}}{2}\\\\SA=\dfrac{2lw+l\sqrt{l^2+4h^2}+w\sqrt{w^2+4h^2}}{2}$

6 0

3 years ago

What is the surface area of the composite figure

leva [86]

Answer:

The answer is 672.

Step-by-step explanation:

To solve this problem, first let's find the surface area of the rectangular prism. To do that, multiply each dimension with each (times 2 | just in case you don't understand [what I'm talking about is down below]).

8 x 8 x 2 = 128

8 x 11 x 2 = 176

Then, add of the products together to find the surface area of the rectangular prism.

176 + 176 + 128 = 480

Now, let's find the surface area of the square pyramid. Now, for this particular pyramid, let's deal with the triangles first, then the square. Like we did with the rectangular prism above, multiply each dimension with each other (but dividing the product by 2 | in case you don't understand [what i'm talking about is down below]).

8 x 8 = 64.

64 ÷ 2 = 32.

SInce there are 4 triangles, multiply the quotient by 4 to find the surface area of the total number of triangles (what i'm talking about is down below).

32 x 4 = 128.

Now, let's tackle the square. All you have to do is find the area of the square.

8 x 8 = 64.

To find the surface area of the total square pyramid, add both surface areas.

128 + 64 = 192.

Finally, add both surface areas of the two 3-D shapes to find the surface area of the composite figure.

192 + 480 = 672.

Therefore, 672 is the answer.

6 0

3 years ago

Hey I need a step by step of this!!! Or can you just explain to me how to figure it out step by step!! either is fine

Umnica [9.8K]

Answer:

I believe the answer may be x= 24.5 I'm not certain though

Step-by-step explanation:

The angles inside the triangle must all add up to 180 so we can subtract 80 from 180 to get 98. Now I'm assuming the two undefined angles are equal because of the two angle bisectors that create the second triangle. If I'm correct in assuming that them we can divided 98 by 2 to get 49 which would be the measurement of both bottom angles. Since there's a line bisecting both of them we would then cut that number in half to get 24.5. I hope this helped, I'm not fully certain of this answer though.

4 0

3 years ago