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3 years ago

Which of these is equal to cos 19°? A) sin 71° B) sin 81° C) cos 71° D) cos 81°

Mathematics

2 answers:

Over [174]3 years ago

7 0

Cos α = sin (90-α) so cos 19 = sin 90-19 = sin 71

LUCKY_DIMON [66]3 years ago

3 0

cos 19° = sin 71°

A: sin 71°

since sin is basically the inverse of cos, you can do 90-19 = 71.

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the area of a rectangle is 90 in2^. the ratio of the length to the width is 5:2. find the length and the width

-BARSIC- [3]

Length and width of rectangle is 15 inches and 6 inches respectively

<h3><u>Solution:</u></h3>

Given that area of a rectangle is 90 square inch

Ratio of length to the width = 5: 2.

Need to determine length and width of rectangle.

As ratio of length to the width is 5 : 2

Lets assume length of rectangle = 5x inches and width of rectangle = 2x inches.

<em><u>The formula for area of rectangle is given as:</u></em>

$\text { Area of rectangle }=\text { length of rectangle } \times \text { width of rectangle}$

Substituting the given value of area of rectangle and assumed value of length and width of rectangle we get:

$\begin{array}{l}{90=5 x \times 2 x} \\\\ {=>90=10 x^{2}}\end{array}$

On solving the above expression for x we get

$\begin{array}{l}{=>\frac{90}{10}=x^{2}} \\\\ {=>x^{2}=9} \\\\ {=>x=\sqrt{9}=3}\end{array}$

$\begin{array}{l}{\text { Length of rectangle }=5 \times x=5 \times 3=15 \text { inches }} \\\\ {\text { Width of rectangle }=2 \times} x=2 \times} 3=6 \text { inches }}\end{array}$

Hence length and width of rectangle is 15 inches and 6 inches.

4 0

4 years ago

HELP ASAP

astra-53 [7]

Answer:

Step-by-step explanation:

We are given a circle with a partially shaded region. First, we need to determine the area of the whole circle. To do this, we need the measurement of the radius of the circle:

Use the Pythagorean theorem to solve for the other leg of the right triangle inside the circle:

5^2 = 3^2 + x^2

x = 4

The radius is 4 + 1 cm = 5 cm

So the area of the circle is A = pi*r^2

A = 3.14 * (5)^2

A = 25pi cm^2

To solve for the area of the shaded region:

Ashaded = Acircle - Atriangles

we need to solve for the area of the triangles:

A = 1/2 *b*h

A = 1/2 *6 * 5

A = 15 cm^2

Atriangles = 2 * 15

Atriangles = 30 cm^2

Ashaded = 25pi - 30

8 0

2 years ago

I need help ASAP. This is multiple choice

kvv77 [185]

Answer:

the answer is 3

Step-by-step explanation:

7 0

3 years ago

Mark and raquel were playing a word game.Raquel played the word math on a game board on a space marked’’triple points’.If her wo

Reika [66]

Answer:

111 points

Step-by-step explanation:

First, thing I like to do is to convert word problems into an eqaution or write down the important information. So, Math = 37 points and now the points are tripled because of where she placed the word. Also, tripled is implying that her base score for the word is 3 times the original value.

So, $37*3$

= 111 points.

5 0

3 years ago

Read 2 more answers

Which expression is equivalent to 4(3+5)-3.94?

Anna007 [38]

Answer:

$4(3 + 5) - 3.94 \\ 4 \times 8 - 3.94 \\ 32 - 3.94 \\ = 28.06$

3 0

3 years ago