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2 years ago

Someone help me please?

Mathematics

2 answers:

AlekseyPX2 years ago

6 0

(r-3)^2 I think this is correct because r^2 means r*r and you are subtracting 9 so I just multiplyed 3*3.

yanalaym [24]2 years ago

4 0

Is a (r + 3) (r - 3)

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Given that CD¯¯¯¯¯¯¯¯ is a perpendicular bisector of AB¯¯¯¯¯¯¯¯, where D is on AB¯¯¯¯¯¯¯¯, how can you use the Pythagorean Theor

Liula [17]

Answer:

$(AD)^2 + (CD)^2 = (CA)^2$ and $(CD)^2 + (BD)^2 = (CB)^2$

Step-by-step explanation:

Given

Bisector: CD

of Line AB

Required

Apply Pythagoras Theorem

From the question, CD bisects AB and it bisects it at D.

The relationship between AB and CD is given by the attachment

Considering ACD

From the attachment, we have that:

$Hypothenuse = CA$

$Opposite = CD$

$Adjacent = AD$

By Pythagoras Theorem, we have

$(AD)^2 + (CD)^2 = (CA)^2$

Considering CBD

From the attachment, we have that:

$Hypothenuse = CB$

$Opposite = CD$

$Adjacent = BD$

By Pythagoras Theorem, we have:

$(CD)^2 + (BD)^2 = (CB)^2$

4 0

3 years ago

Read 2 more answers

webassign If a snowball melts so that its surface area decreases at a rate of 6 cm2/min, find the rate at which the diameter dec

drek231 [11]

Answer:

The answer is $\frac{3}{10\pi } cm/min$

Step-by-step explanation:

Assuming the snowball is a perfect sphere, then if A denotes the surface area and D the diameter then:

$A=4\pi r^{2} = 4\pi (\frac{D}{2} )^{2} =\pi D^{2}$

Differentiating wrt r we have:

$\frac{dA}{dD} =2\pi D$

We are told that $\frac{dA}{dt}= -6$ and we want to find $\frac{dD}{dt}$

By the chain rule we have:

$\frac{dA}{dD}=\frac{dA}{dt}.\frac{dt}{dD}=\frac{\frac{dA}{dt} }{\frac{dD}{dt} }$

∴ $2\pi D=-\frac{6}{\frac{dD}{dt} }$

∴ $\frac{dD}{dt}=-\frac{6}{2\pi D}$

When D=10 then

$\frac{dD}{dt} =-\frac{6}{10*2\pi } =-\frac{3}{10\pi }$

The sign (-) shows that the D is decreasing.

3 0

3 years ago

Find the surface area of the triangular prism

melomori [17]

Answer:

608 ft²

Step-by-step explanation:

1) Find the area of the bases

$A=\frac{1}{2} bh$ where b is the base length and h is the height

Plug in b and h

$A=\frac{1}{2} (12)(8)\\A=48$

Multiply the answer by 2 (because there are 2 bases)

A=96

Therefore, the area of the two bases is 96 ft².

2) Find the area of the two sides facing up

$A=lw$ where l is the length and w is the width

Plug in l and w

$A=10*16\\A=160$

Multiply the answer by 2 (because there are 2 sides)

A=320

Therefore, the area of these two sides is 320 ft².

3) Find the area of the bottom side

$A=lw$ where l is the length and w is the width

Plug in l and w

$A=12*16\\A=192$

Therefore, the area of this side is 192 ft².

4) Add all the areas together

96 ft² + 320 ft² + 192 ft²

= 608 ft²

Therefore, the surface area of the triangular prism is 608 ft².

I hope this helps!

5 0

3 years ago

Read 2 more answers

100x^2-4=0 quick pls with all work

Finger [1]

4(5x+1)(5x-1) = 0

1. Take out the GCF (in this case, 4)
4(25x^2-1) = 0

2. This can be further factored. Factor the values within the parenthesis
4(5x + 1)(5x -1) = 0

4 0

2 years ago

Read 2 more answers

Determine the volume of the tent?

katovenus [111]

Answer:

6(base) x 3.5(Height) = 21, 21 divided by 2 (x 1/2) = 10.5

10.5(area of triangle) x 7.75(width) = 81.375

Formula of an area of a triangle:

BH x 1/2

Base x Height x 1/2(basically just dividing by 2)

Now the base:

1.5 x 7.75 x 6 = 69.75

Now let's add the two given volumes:

81.375+ 69.75 = 151.125 ft^3 is your answer.

5 0

3 years ago