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4 years ago

Help...I not understand

Mathematics

1 answer:

natali 33 [55]4 years ago

6 0

2a + 2b = The perimeter. You know one side (5cm) and the total perimeter (30cm)So your equation should be 2(5) + 2(b) = 30. From here you simply solve for "b" 2(b) = 30 -10 2(b) = 20 b = 20/2 b is equal to 10cm.

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If a triangle has side lengths of 14 centimeters and 18 centimeters and the perimeter is 49 centimeters, how long is the third s

trasher [3.6K]

Answer: 17 centimeters

Step-by-step explanation:

The perimeter of a triangle is all 3 sides added up

x+y+z=p

Substitute 14 in for x, 18 in for y and 49 in for p

14+18+z=49

Add on the left side

32+z=49

Subtract 32 on both sides

z=17

So, the third side is 17 centimeters

Hope this helps! :)

3 0

3 years ago

If cos() = − 2 3 and is in Quadrant III, find tan() cot() + csc(). Incorrect: Your answer is incorrect.

nydimaria [60]

Answer:

$\tan(\theta) \cdot \cot(\theta) + \csc(\theta) = \frac{5 - 3\sqrt 5}{5}$

Step-by-step explanation:

Given

$\cos(\theta) = -\frac{2}{3}$

$\theta \to$ Quadrant III

Required

Determine $\tan(\theta) \cdot \cot(\theta) + \csc(\theta)$

We have:

$\cos(\theta) = -\frac{2}{3}$

We know that:

$\sin^2(\theta) + \cos^2(\theta) = 1$

This gives:

$\sin^2(\theta) + (-\frac{2}{3})^2 = 1$

$\sin^2(\theta) + (\frac{4}{9}) = 1$

Collect like terms

$\sin^2(\theta) = 1 - \frac{4}{9}$

Take LCM and solve

$\sin^2(\theta) = \frac{9 -4}{9}$

$\sin^2(\theta) = \frac{5}{9}$

Take the square roots of both sides

$\sin(\theta) = \±\frac{\sqrt 5}{3}$

Sin is negative in quadrant III. So:

$\sin(\theta) = -\frac{\sqrt 5}{3}$

Calculate $\csc(\theta)$

$\csc(\theta) = \frac{1}{\sin(\theta)}$

We have: $\sin(\theta) = -\frac{\sqrt 5}{3}$

So:

$\csc(\theta) = \frac{1}{-\frac{\sqrt 5}{3}}$

$\csc(\theta) = \frac{-3}{\sqrt 5}$

Rationalize

$\csc(\theta) = \frac{-3}{\sqrt 5}*\frac{\sqrt 5}{\sqrt 5}$

$\csc(\theta) = \frac{-3\sqrt 5}{5}$

So, we have:

$\tan(\theta) \cdot \cot(\theta) + \csc(\theta)$

$\tan(\theta) \cdot \cot(\theta) + \csc(\theta) = \tan(\theta) \cdot \frac{1}{\tan(\theta)} + \csc(\theta)$

$\tan(\theta) \cdot \cot(\theta) + \csc(\theta) = 1 + \csc(\theta)$

Substitute: $\csc(\theta) = \frac{-3\sqrt 5}{5}$

$\tan(\theta) \cdot \cot(\theta) + \csc(\theta) = 1 -\frac{3\sqrt 5}{5}$

Take LCM

$\tan(\theta) \cdot \cot(\theta) + \csc(\theta) = \frac{5 - 3\sqrt 5}{5}$

6 0

3 years ago

Please help me I need this in like 10min

Gre4nikov [31]

Answer:

1. congreunt; reflection

2. not congruent

3. congruent; rotation & translation

4. 64 cm

5. 62 degrees

Step-by-step explanation:

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3 years ago

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Solve correctly and I’ll give brainliest.

Lera25 [3.4K]

Answer:

Step-by-step explanation:

-2 x 6 = -12

-6/1 ÷ -3/1 = 2

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-14 ÷ -2 = 7

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3 years ago

11×12=(10+1)×(10+2)what property dose this demonstrate

Natasha2012 [34]

This demonstrates the associative property

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4 years ago

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