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3 years ago

Determine (a) the area and (b) the circumference of the circle.

Mathematics

1 answer:

Inga [223]3 years ago

3 0

Step-by-step explanation:

To find the area of the circle we must first find the radius using the formula

radius = diameter / 2

From the question

diameter = 21 ft

The radius is

21/2 = 10.5 ft

Area of a circle = πr²

where r is the radius

Area = π(10.5)²

= 110.25π

Circumference of a circle = πd

where d is the diameter

Circumference = π(21)

Hope this helps you

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Which scenarios can be represented by a ratio of 4 : 5 ?

KonstantinChe [14]

Answer:

There are many scenario's.

Step-by-step explanation:

1.4:5

2.4/5

3.4÷5

5 0

2 years ago

Read 2 more answers

Pls guys help me pls

galina1969 [7]

Answer:

$x < 5$

I think the answer is A

8 0

3 years ago

The shorter leg of a right triangle is 7cm shorter than the longer leg. The hypotenuse is 7cm longer then the linger leg. What i

Gelneren [198K]

The shorter leg is 21cm, longer leg is 28 cm and hypotenuse is 35cm.

Step-by-step explanation:

Let,

The longer leg = x

The shorter leg = x-7

Hypotenuse = x+7

Using Pythagoras theorem;

$a^2+b^2=c^2\\(x-7)^2+(x)^2=(x+7)^2\\x^2-14x+49+x^2=x^2+14x+49\\2x^2-14x+49-x^2-14x-49=0\\x^2-28x=0\\x(x-28)=0\\$

Either,

x= 0

Or,

x-28=0 =>x=28

As length cannot be zero, therefore,

Longer side = 28cm

Shorter side = x-7 = 28-7 = 21cm

Hypotenuse = x+7 = 28+7 = 35cm

The shorter leg is 21cm, longer leg is 28 cm and hypotenuse is 35cm.

Keywords: triangle, pythagoras theorem

Learn more about triangles at:

#LearnwithBrainly

5 0

3 years ago

Red and grey bricks were used to build a decorative wall. The number of red bricks and grey bricks was 5/2. There were 140 brick

ozzi

Answer:

100 red bricks

Step-by-step explanation:

Let's say red bricks is equal to 5x

Gray bricks is equal to 2x

We have an equation

2x + 5x = 140

= 7x = 140

Divide through by 7 to get the value of x

X = 140/7

X = 20

Red bricks = 5(x)

= 5(20)

= 100

Gray bricks = 2(x)

= 2(20)

= 40

Therefore in conclusion the number of red bricks is 100.

5 0

2 years ago

How many terms are in the expression 6w- 3x+9y- 8z+ 12

kirill [66]

Answer:

Step-by-step explanation:

<u>Definition of term:</u>

A term is a single mathematical expression. It may be a single number (positive or negative), a single variable ( a letter ), several variables multiplied but never added or subtracted.

6w- 3x+9y- 8z+ 12

6w - 3x +9y - 8z + 12

Hope this helps, have a nice day! :D

8 0

2 years ago