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2 years ago

Help me please!! thank you!

Mathematics

1 answer:

pychu [463]2 years ago

6 0

Answer:

45.5cm

Step-by-step explanation:

70/20 = 3.5cm per book

20- 7 = 13

13 x 3.5 = 45.5cm

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The area of the square is greater than the area of the circle.

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Is the centre of a circle always equal distance from all points on the circumference? and why

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Two lines are intersecting. What is the value of x? Enter your answer in the box. (x + 23) (2x + 4)° Help! Please!!!

Delicious77 [7]

Answer:

$x = 51^o$

Step-by-step explanation:

Given

Intersecting lines

Required

Find x

To do this, we make use of:

$x + 23^o + 2x + 4^o = 180^o$ --- angle on a straight line

Collect like terms

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5 0

2 years ago

The perimeter of equilateral triangle ABC is 81/3 centimeters, find the length of the radius and apothem.

MAXImum [283]

There is a typo error, the perimeter of equilateral triangle ABC is 81/√3 centimeters.

Answer:

Radius = OB= 27 cm

Apothem = 13.5 cm

A diagram is attached for reference.

Step-by-step explanation:

Given,

The perimeter of equilateral triangle ABC is 81/√3 centimeters.

Substituting this in the formula of perimeter of equilateral triangle = $3\times\ side$

$3\times\ side$ $=[tex]81\sqrt{3}$

$Side = \frac{81\sqrt{3} }{3} =27\sqrt{3} \ cm$

Thus from the diagram , Side $AB=BC=AC= 27\sqrt{3} \ cm$

We know each angle of an equilateral triangle is 60°.

From the diagram, OB is an angle bisector.

Thus $\angle OBC = 30$ °

Apothem is the line segment from the mid point of any side to the center the equilateral triangle.

Therefore considering ΔOBE, and applying tan function.

$tan\theta =\frac{perpendicular}{base} \\tan\theta=\frac{OE}{BE} \\tan\theta=\frac{OE}{\frac{27\sqrt{3}}{2} } \\tan30\times {\frac{27\sqrt{3} }{2} }= OE\\\frac{1}{\sqrt{3} } \times\frac{27\sqrt{3} }{2} =OE\\$

Thus ,apothem OE= 13.5 cm

Now for radius,

We consider ΔOBE

$cos\theta=\frac{base}{hypotenuse} \\cos30= \frac{BE}{OB} \\Cos30 = \frac{\frac{27\sqrt{3} }{2}}{OB} \\OB= \frac{\frac{27\sqrt{3} }{2}}{cos30} \\OB= \frac{\frac{27\sqrt{3} }{2}}{\frac{\sqrt{3} }{2} } \\OB =27 \ cm$

Thus for

Perimeter of equilateral triangle ABC is 81/√3 centimeters,

The radius of equilateral triangle ABC is 27 cm

The apothem of equilateral triangle ABC is 13.5 cm

4 0

2 years ago

The price of pair of shoes is $63.20. The sales tax rate is 4.5 percent. How much sales tax would you pay if you bought these sh

olga nikolaevna [1]

The answer to the problem is as follows:

We can convert 4.5% into a decimal form by moving the decimal to the left two places. This becomes: .045

<span>63.20 x .045 = $2.84

</span>I hope my answer has come to your help. God bless and have a nice day ahead!

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2 years ago

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