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3 years ago

Make COS the subject of the formula

Mathematics

1 answer:

docker41 [41]3 years ago

6 0

c^2 = a^2 + b^2 - 2(ab)(cos C)

c^2 + 2(ab)(cos C) = a^2 + b^2

2(ab)(cos C) = a^2 + b^2 - c^2

cos C = (a^2 + b^2 - c^2) / 2ab - Answer choice E

Hope this helps! :)

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Please please help me with this

Olegator [25]

Answer:

Step-by-step explanation:

First find the equations of the lines, then fill in the proper inequality sign. The upper line has a y-intercept of 1 and a slope of 1/2, so the equation, in slope-intercept form is

$y=\frac{1}{2}x+1$

Since the shading is below the line, the inequality sign is less than or equal to. The inequality, then, is

$y\leq \frac{1}{2}x+1$

But the solutions are in standard form, so let's do that:

$-\frac{1}{2}x+y\leq 1$

AND they do not like to lead with negatives, apparently, so let's change the signs and the way the inequality is facing, as well:

$\frac{1}{2}x-y\geq -1$

Let's do the sae with the lower line. The equation, in slope-intercept form is

$y=\frac{3}{2}x-3$ since the slope is 3/2 and the y-intercept is -3. Now, since the shading is above the line, the inequality is greater than or equal to:

$y\geq \frac{3}{2}x-3$

In standard form:

$-\frac{3}{2}x+y\geq -3$ and not leading with a negative gives us

$\frac{3}{2}x-y\leq 3$

Those 2 solutions are in choice B, I do believe.

7 0

4 years ago

Every year, roughly 25,000,000 kg of hair is cut in the United States. Each kilogram of hair contains about 0.0002 kg of zinc, a

Nesterboy [21]

$20,000

25,000,000 x 0.0002 = 5,000

5,000 x $4.00= $20,000

4 0

3 years ago

Perform the indicated operation.<br>1/5+3/5

Vesnalui [34]

Answer:

because we have the same denominator, it will be 4/5

Step-by-step explanation:

6 0

3 years ago

Read 2 more answers

B ^ 2 - 4b - 14 = 0

Blizzard [7]

Simplifying
b2 + -4b + -14 = 0

Reorder the terms:
-14 + -4b + b2 = 0

Solving
-14 + -4b + b2 = 0

Solving for variable 'b'.

Begin completing the square.

Move the constant term to the right:

Add '14' to each side of the equation.
-14 + -4b + 14 + b2 = 0 + 14

Reorder the terms:
-14 + 14 + -4b + b2 = 0 + 14

Combine like terms: -14 + 14 = 0
0 + -4b + b2 = 0 + 14
-4b + b2 = 0 + 14

Combine like terms: 0 + 14 = 14
-4b + b2 = 14

The b term is -4b. Take half its coefficient (-2).
Square it (4) and add it to both sides.

Add '4' to each side of the equation.
-4b + 4 + b2 = 14 + 4

Reorder the terms:
4 + -4b + b2 = 14 + 4

Combine like terms: 14 + 4 = 18
4 + -4b + b2 = 18

Factor a perfect square on the left side:
(b + -2)(b + -2) = 18

Calculate the square root of the right side: 4.242640687

Break this problem into two subproblems by setting
(b + -2) equal to 4.242640687 and -4.242640687. b + -2 = 4.242640687

Simplifying
b + -2 = 4.242640687

Reorder the terms:
-2 + b = 4.242640687

Solving
-2 + b = 4.242640687

Solving for variable 'b'.

Move all terms containing b to the left, all other terms to the right.

Add '2' to each side of the equation.
-2 + 2 + b = 4.242640687 + 2

Combine like terms: -2 + 2 = 0
0 + b = 4.242640687 + 2
b = 4.242640687 + 2

Combine like terms: 4.242640687 + 2 = 6.242640687
b = 6.242640687
Simplifying
B = 6.242640687

Subproblem 2
b + -2 = -4.242640687

Simplifying
b + -2 = -4.242640687

Reorder the terms:
-2 + b = -4.242640687

Solving
-2 + b = -4.242640687

Solving for variable 'b'.

Move all terms containing b to the left, all other terms to the right.

Add '2' to each side of the equation.
-2 + 2 + b = -4.242640687 + 2

Combine like terms: -2 + 2 = 0
0 + b = -4.242640687 + 2
b = -4.242640687 + 2

Combine like terms: -4.242640687 + 2 = -2.242640687
b = -2.242640687

Simplifying
b = -2.242640687

3 0

3 years ago

Read 2 more answers

What is -2<img src="https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B2%7D" id="TexFormula1" title="\frac{1}{2}" alt="\frac{1}{2}" align=

dolphi86 [110]

well, you already know how to convert from mixed to improper, so let's simply do the division.

$\bf -2\frac{1}{2}\div 6\implies -\cfrac{5}{2}\div 6\implies \cfrac{-5}{2}\div \cfrac{6}{1}\implies \cfrac{-5}{2}\cdot \cfrac{1}{6}\implies -\cfrac{5}{12}$

7 0

3 years ago