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3 years ago

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Dr. Black is standing 15 feet from a streetlamp. The lamp is making his shadow 8 feet long. He estimates that the angle of eleva

tion from the tip of his shadow to the top of the street lamp 50 degrees. To the nearest foot, the streetlamp is about

1 answer:

Stella [2.4K]3 years ago

6 0

Check the picture below.

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Venita is factoring the expression 32ab-8b. She determines the GCF and writes the factored expression as 8b(4a-0). Which best de

Nimfa-mama [501]

Let's go through the steps of factoring that Venita should take.

1.) Find the greatest common factor (GCF). We only have two terms, so that makes it pretty easy.
32 = 1, 2, 4, 8, 16, 32
8 = 1, 2, 4, 8
The greatest common factor of 32 and 8 is 8. We can also factor out a <em>b</em> since that term appears in each part of the original expression. The GCF and variable should go on the outside of the parentheses.
8b( )

2.) Now let's figure out what should go in the middle of the parentheses. To do this, use the original expression and divide each term. This is written in the parentheses.

32ab ÷ 8b = 4a
8b ÷ 8b = 1

This would then result in the factored expression 8b(4a - 1). You can always check this by using the distributive property. Distribute 8b out to both expressions:
8b x 4a = 32ab
8b x 1 = 8b
32ab - 8b is the expression she started with, so your factored expression works!

Now that we went through the steps to solve the factored expression, let's check her answer. The only difference between Venita's and ours is that she has 0 as the second term while we have a 1. It seems that she had subtracted the GCF from the second term instead of dividing.

6 0

3 years ago

Read 2 more answers

Pls show full working out

sweet-ann [11.9K]

Answer:

Question 1a. i) $x=1.8m$

Question 1a. ii) $Volume=27.6m^3$

Question 1b) $Volume=65.9m^3$

Explanation:

<u><em>Question 1 a. i) Find the value of x.</em></u>

$tan(\theta )=\dfrac{opposite\text{ }leg}{adjacent\text{ }leg}$

For the smalll triangle you can write:

$tan(\theta )=\dfrac{x}{1m}$

For tthe big triangle:

$tan(\theta )=\dfrac{x+2.7m}{2.5m}$

Substitute:

$\dfrac{x}{1m}=\dfrac{x+2.7m}{2.5m}$

Solve for x:

$2.5x=x+2.7m\\\\2.5x-x=2.7m\\\\1.5x=2.7m\\\\x=2.7m/1.5\\\\x=1.8m$

<u><em>Question 1a ii) Find the volume of the frustrum</em></u>

Find the volume of a cone with height = 2.7m + 1.8m = 4.5m, and radius = 2.5m

Formula:

$Volume=(1/3)\pi \times radius^2\times height$

Substitute:

$Volume=(1/3)\pi \times (2.5m)^2\times 4.5m=9.375\pi m^3$

Find the volume of a cone with heigth = 1.8m and radius = 1m

$Volume=(1/3)\pi \times (1m)^2\times 1.8m=0.6\pi m^3$

Subtract the volume of the small cone from the volume of the big cone

$Volume\text{ }of\text{ }frustrum=9.375\pi m^3-0.6\pi m^3=8.775\pi m^3\approx 27.6m^3$

<u><em>Question 1b. Calculate the volume of the bin</em></u>

<u>i) Upper frustrum</u>

This is the same frustrum from the equation of above, thus ist volume is 27.6m³.

<u>ii) Lower frustrum</u>

$\dfrac{x}{2.0m}=\dfrac{x+2.4m}{2.5m}$

$2.5x=2(x+2.4m)\\\\2.5x=2x+4.8m\\\\0.5x=4.8m\\\\x=9.6m$

$Volume=(1/3)\pi \times (2.5m)^2\times (9.6m+2.4m)-(2.0m)^2\times (9.6m)$

$Volume=38.3m^3$

<u>iii) Add the volume of the two frustrums</u>

$Volume=27.6m^3+38.3m^3=65.9m^3$

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What is the rectangular form of z = 6(cos((3pi)/4) + i sin((3pi)/4))

kvv77 [185]

Answer:

Z= -3 square root 2 + 3i square root 2

Step-by-step explanation:

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BRAINIEST TO WHOEVER RIGHT

victus00 [196]

Answer:

8

Step-by-step explanation:

To find the median, look at the line in the box. it lines up with 8 on the number line. Therefore, 8 is the median.

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Identifying the Constant Rate of Change from a Table

Dmitry [639]

Answer:

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Step-by-step explanation:

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