-5(c+4) +25+7c please hurry

State one form of the Law of Cosines and provide a trick for writing the other two forms and explain when Law of Cosines should

Yuki888 [10]

Solving for Angles

$\displaystyle \frac{a^2 + b^2 - c^2}{2ab} = cos∠C \\ \frac{a^2 - b^2 + c^2}{2ac} = cos∠B \\ \frac{-a^2 + b^2 + c^2}{2bc} = cos∠A$

* Do not forget to use the inverse function towards the end, or elce you will throw your answer off!

Solving for Edges

$\displaystyle b^2 + a^2 - 2ba\:cos∠C = c^2 \\ c^2 + a^2 - 2ca\:cos∠B = b^2 \\ c^2 + b^2 - 2cb\:cos∠A = a^2$

You would use this law under two conditions:

One angle and two edges defined, while trying to solve for the third edge
ALL three edges defined

* Just make sure to use the inverse function towards the end, or elce you will throw your answer off!

_____________________________________________

Now, JUST IN CASE, you would use the Law of Sines under three conditions:

Two angles and one edge defined, while trying to solve for the second edge
One angle and two edges defined, while trying to solve for the second angle
ALL three angles defined [of which does not occur very often, but it all refers back to the first bullet]

* I HIGHLY suggest you keep note of all of this significant information. You will need it going into the future.

I am delighted to assist you at any time.

7 0

3 years ago

Find the values of x and y. Leave answers in simplest radical form.

NNADVOKAT [17]

$\sin(60°) = \frac{x}{14} \Leftrightarrow x = 14 \sin(60°) = \frac{14 \sqrt{3} }{2} = 7 \sqrt{3} \\ \cos(60°) = \frac{y}{14} \Leftrightarrow y = 14\cos(60°) = \frac{14}{2} = 7$

6 0

3 years ago

Find the width of the rectangular prism when the surface area is 208 square centimeters.

ozzi

SA=2(lw+wh+lh) This is the formula for finding the surface area of a rectangular prism, where SA is surface area, l is length, w is width, and h is height.

208=2(lw+wh+lh)
104=lw+wh+lh Here, I divided both sides by 2 to get ride of the 2.

Now, I used prime factorization to find out all the prime factors of 104, which are 2, 2, 2, and 13. Since rectangular prisms only have 3 dimensions, I needed to combine two of the prime factors. In this case, I can either combine 2 of the 2s to get 2, 4, and 13 or I can combine 13 with one of the 2s to get 26, 2, and 2.

If my dimensions were 2, 4, and 13...
my surface area would be 172 sq cm.

If my dimensions were 2, 2, and 26...
my surface area would be 208 sq cm.

Hence, the width of the rectangular prism when the surface area is 208 square centimeters can be either 2 or 26.

7 0

4 years ago

Point m is the midpoint of ab and b is the midpoint of ac what are the values of x and y

Gemiola [76]

In which point you want the value of x and y

4 0

3 years ago

How do I solve a piece wise function

romanna [79]

If there's a constant value like k or c as well as x, then you have to set each equation equal to each other and plug in the restriction for x. So if x is less than or equal to 2, you plug in two! Then use algebra to solve for k or c!!

4 0

3 years ago