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4 years ago

B. 14

Mathematics

1 answer:

Serga [27]4 years ago

4 0

Answer:

Step-by-step explanation:

5x + 7x - 18x = 12x - 18x = -6x

answer is C

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PLEASE HELP ME!! GIVING BRAINLIEST AND 5 STARS

Marizza181 [45]

4(x+2)=4x+8
2(x-1)=2x-2
2(x+1)=2x+2

You use disruptive property when solving equations like this.

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2 years ago

Evaluate 18 divided 2a if a = 3

Andreas93 [3]

Answer:

Step-by-step explanation:

$\frac{18}{2a}$

a = 3

$\frac{18}{2(3)}$

multiply 2 and 3

2 * 3 = 6

$\frac{18}{6}$

simplify

18/6 = 3

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3 years ago

If the sin 90° = 1, then the cos 0° = _____. (1 point)

Cloud [144]

sin 90° = 1

cos 0° = 1

There's a simple formula : sin θ = cos (90°- θ) or cos θ = sin (90°- θ) 

So : cos 0° = sin (90° - 0°) = sin 90° = 1

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3 years ago

Read 2 more answers

Simplify completely the quantity 4 times x to the third power plus 5 times x to the 2nd power plus 3 times x all over x. (2 poin

julia-pushkina [17]

We start with

$\dfrac{4x^3+5x^2+3x}{x}$

We can factor x at the numerator:

$\dfrac{x(4x^2+5x+3)}{x}$

So, assuming $x\neq 0$ (otherwise the expression would make no sense) we can simplify it:

$\dfrac{x(4x^2+5x+3)}{x} = 4x^2+5x+3$

This equation has no roots, so we can't simplify it any further.

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3 years ago

Find , , and if and terminates in quadrant .

ioda

sin2x =12/13

cos2x = 5/13

tan2x = 12/5

STEP - BY - STEP EXPLANATION

What to find?

• sin2x

• cos2x

• tan2x

Given:

tanx = 2/3 = opposite / adjacent

We need to first make a sketch of the given problem.

Let h be the hypotenuse.

We need to find sinx and cos x, but to find sinx and cosx, first determine the value of h.

Using the Pythagoras theorem;

hypotenuse² = opposite² + adjacent²

h² = 2² + 3²

h² = 4 + 9

h² =13

Take the square root of both-side of the equation.

h =√13

This implies that hypotenuse = √13

We can now proceed to find the values of ainx and cosx.

Using the trigonometric ratio;

$\sin x=\frac{opposite}{\text{hypotenuse}}=\frac{2}{\sqrt[]{13}}$ $\cos x=\frac{adjacent}{\text{hypotenuse}}=\frac{3}{\sqrt[]{13}}$

And we know that tanx =2/3

From the trigonometric identity;

sin 2x = 2sinxcosx

Substitute the value of sinx , cosx and then simplify.

$\sin 2x=2(\frac{2}{\sqrt[]{13}})(\frac{3}{\sqrt[]{13}})$ $=\frac{12}{13}$

Hence, sin2x = 12/13

cos2x = cos²x - sin²x

Substitute the value of cosx, sinx and simplify.

$\begin{gathered} \cos 2x=(\frac{3}{\sqrt[]{13}})^2-(\frac{2}{\sqrt[]{13}})^2 \\ \\ =\frac{9}{13}-\frac{4}{13} \\ =\frac{5}{13} \end{gathered}$

Hence, cos2x = 5/13

tan2x = 2tanx / 1- tan²x

$\tan 2x=\frac{2\tan x}{1-\tan ^2x}$ $=\frac{2(\frac{2}{3})}{1-(\frac{2}{3})^2}$ $=\frac{\frac{4}{3}}{1-\frac{4}{9}}$ $=\frac{\frac{4}{3}}{\frac{9-4}{9}}$ $=\frac{\frac{4}{3}}{\frac{5}{9}}$ $=\frac{4}{3}\times\frac{9}{5}=\frac{4}{1}\times\frac{3}{5}=\frac{12}{5}$

$\tan 2x=\frac{\sin 2x}{\cos 2x}=\frac{\frac{12}{13}}{\frac{5}{13}}=\frac{12}{5}$

Hence, tan2x = 12/5

Therefore,

sin2x =12/13

cos2x = 5/13

tan2x = 12/5

3 0

1 year ago