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2 years ago

Work out the area of this semicircle with radius 3cm give your answer in terms of pie

Mathematics

2 answers:

azamat2 years ago

5 0

Answer:

Answer=4.5π

Step-by-step explanation:

you square 3 and then divide it by 2 and then just add pi

Hitman42 [59]2 years ago

3 0

Answer:

A=4.5π

The formula for finding a circle is A=πr² so just plug in the value for the radius. Don't forget to divide the entire thing by 2 when you finish, cos it's a semi circle (which is a half circle)

Step-by-step explanation:

Cos Milky Said it.

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Choose the equation of a line that is perpendicular to the y-axis and passes through the point (5, -2).

Irina-Kira [14]

It would moat likly be y=-2 due to it having to be perpendicular to the y axis and pass through the 5,-2 point

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2 years ago

What is the are of this circle 8cm

Fantom [35]

Answer:

64π(cm)2

Step-by-step explanation:

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3 years ago

Read 2 more answers

−3 2/3=x−1 1/4 pls help

slega [8]

Answer:

- 2 5/12

Step-by-step explanation:

−3 2/3 = x − 1 1/4
x = - 3 2/3 + 1 1/4
x = - 2 - 2/3 + 1/4
x = - 2 - 8/12 + 3/12
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8 0

2 years ago

A school wishes to enclose its rectangular playground using 480 meters of fencing.

Harlamova29_29 [7]

Answer:

Part a) $A(x)=(-x^2+240x)\ m^2$

Part b) The side length x that give the maximum area is 120 meters

Part c) The maximum area is 14,400 square meters

Step-by-step explanation:

The picture of the question in the attached figure

Part a) Find a function that gives the area A(x) of the playground (in square meters) in terms of x

we know that

The perimeter of the rectangular playground is given by

$P=2(L+W)$

we have

$P=480\ m\\L=x\ m$

substitute

$480=2(x+W)$

solve for W

$240=x+W\\W=(240-x)\ m$

<u><em>Find the area of the rectangular playground</em></u>

The area is given by

$A=LW$

we have

$L=x\ m\\W=(240-x)\ m$

substitute

$A=x(240-x)\\A=-x^2+240x$

Convert to function notation

$A(x)=(-x^2+240x)\ m^2$

Part b) What side length x gives the maximum area that the playground can have?

we have

$A(x)=-x^2+240x$

This function represent a vertical parabola open downward (the leading coefficient is negative)

The vertex represent a maximum

The x-coordinate of the vertex represent the length that give the maximum area that the playground can have

Convert the quadratic equation into vertex form

$A(x)=-x^2+240x$

Factor -1

$A(x)=-(x^2-240x)$

Complete the square

$A(x)=-(x^2-240x+120^2)+120^2$

$A(x)=-(x^2-240x+14,400)+14,400$

$A(x)=-(x-120)^2+14,400$

The vertex is the point (120,14,400)

therefore

The side length x that give the maximum area is 120 meters

Part c) What is the maximum area that the playground can have?

we know that

The y-coordinate of the vertex represent the maximum area

The vertex is the point (120,14,400) -----> see part b)

therefore

The maximum area is 14,400 square meters

Verify

$x=120\ m$

$W=(240-120)=120\ m$

The playground is a square

$A=120^2=14,400\ m^2$

8 0

3 years ago

Which can't be lenght side of triangle

Luda [366]

Answer:

C. sides of 3, 4 and 7

can't form a triangle.

the longest side (7) must be shorter than the sum of the other 2 sides.

Step-by-step explanation:

5 0

3 years ago