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3 years ago

Please help evaluate this and turn into a fraction

Mathematics

1 answer:

madam [21]3 years ago

6 0

Answer:

The correct answer is marked.

Step-by-step explanation:

You are given the cosine of an angle, and asked to find the corresponding sine. The relation is ...

sin(x)² = 1 - cos(x)²

sin(x)² = 1 - (-4/√305)² = 1 - 16/305 = 289/305

sin(x) = √(289/305) = 17/√305

The arccos function will return an angle in the first or second quadrant. This negative cosine corresponds to a 2nd-quadrant angle. The sine is positive in the second quadrant.

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Hey guys how do u do 10+10? i forgot :(

Usimov [2.4K]

It’s 20
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4 0

4 years ago

Read 2 more answers

The dimensions of a rectangular garden were 4m by 5m. Each dimension was increased by the same amount the garden then had an are

pogonyaev

The dimension of new garden is 7 meter by 8 meter

Solution:

The dimensions of a rectangular garden were 4m by 5m

Length = 4 m

Width = 5 m

Each dimension was increased by the same amount the garden then had an area of 56 square meter

Let "x" be the amount of increase

Then,

Length = 4 + x

Width = 5 + x

Also, given that,

New area = 56 square meter

The area of rectangle is given as:

$Area = length \times width$

Substituting the values we get,

$56 = (4+x)(5+x)\\\\56 = 20 + 4x + 5x + x^2\\\\x^2 + 9x + 20 - 56 = 0\\\\x^2 + 9x -36=0$

Let us solve the above equation by quadratic formula

$\text {For a quadratic equation } a x^{2}+b x+c=0, \text { where } a \neq 0\\\\x=\frac{-b \pm \sqrt{b^{2}-4 a c}}{2 a}$

Using the above formula,

$\text{For } x^2+9x-36 \text{ we get , }$

a = 1 and b = 9 and c = -36

Substituting the values of a = 1 ; b = 9 ; c = -36 in above quadratic formula we get,

$x = \frac{-9\pm \sqrt{9^2-4\cdot \:1\left(-36\right)}}{2\cdot \:1}\\\\x = \frac{-9\pm \sqrt{81+144}}{2}\\\\x = \frac{-9 \pm 15}{2}$

We get two solutions,

$x = \frac{-9+15}{2} \text{ or } x = \frac{-9-15}{2}\\\\x = 3 \text{ or } x = -12$

Since dimension cannot be negative, ignore x = -12

Thus solution is x = 3

Length = 4 + x = 4 + 3 = 7

Width = 5 + x = 5 + 3 = 8

Thus dimension of new garden is 7 meter by 8 meter

5 0

3 years ago

Find the length of the third side. If necessary, round to the nearest tenth. 10 14

abruzzese [7]

Answer:

9.8 units

Explanation:

According to Pythagoras theorem, the square of length of the hypotenuse is equal to the sum of squares of lengths of other two sides.

Let the third side be x units.

Then,

x² + 10² = 14²

=> x² + 100 = 196

=> x² = 196 - 100

=> x² = 96

=> x = √96

=> x = 4√6

=> x = 9.79....

=> x = 9.8 (Rounding to the nearest tenths)

So, the length of the third side is 9.8 units.

5 0

3 years ago

PLEASE HELP 25 X 120 y = [ ?]

lukranit [14]

Answer:

the sum of one interior angle and one exterior angle is 180

x+120=180

x=180-120

x=60°

sum of angles in a triangle is 180

y+60+25=180

y+85=180

y=180-85

y=95°

3 0

3 years ago

Find the next five terms 512 256 128 64

Alborosie

The pattern is dividing by 2.

512, 256, 128, 64

512/2 = 256, 256/2 = 128, 128/2 = 64

64/2 = 32, 32/2 = 16, 16/2 = 8, 8/2 = 4, 4/2 = 2, ...

6 0

3 years ago