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3 years ago

What happens to the Law of Cosines if the known angle is 90 degrees?

Mathematics

1 answer:

poizon [28]3 years ago

8 0

Answer:

See below.

Step-by-step explanation:

It transforms to the Pythagoras theorem.

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

If C = 90, cos C = zero so the last term disappears.

c^2 = a^2 + b^2 - 2ab * 0

c^2 = a^2 + b^2.

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If 3a = cosec x and 3/a = cot x, find the value of 3(a2 - 1/a2)

insens350 [35]

$\csc(x) = \frac{r}{y} = \frac{3a}{1} \\ \cot(x) = \frac{x}{y} = \frac{3}{a} \\ y = a = 1 \\ \\ 3( {a}^{2} - \frac{1}{{a}^{2} } ) \\ 3( {1}^{2} - \frac{1}{ {1}^{2} } ) \\ = 0$

3 0

3 years ago

Hiw can i reduce my fraction 11/7 int a lower fraction

Dmitry [639]

Answer:

11/7 is the lowest the fraction can be reduced.

Step-by-step explanation:

Since the numerator and denominator don't have a common factor that they can be divided by, the fraction is already simplified.

4 0

3 years ago

Read 2 more answers

PLEASE HELP!! (Look at photo)

Mila [183]

Answer:

10 x (p+2) = 30

10 x 2 = 20 30 - 20 = 10 10 ÷ 10 = 1

P = 1

10 x (1 + 2) = 30

5 0

3 years ago

On a coordinate plane, rectangle E F G H has points (2, 3), (5, 3), (5, 2), (2, 2).

ollegr [7]

Answer: (3,-5)

Step-by-step explanation:

It is

8 0

3 years ago

Read 2 more answers

Any help?? I’ve tried this for a hour and couldn’t figure anything out

Effectus [21]

Answer:

3. PR=51

4. FE=28

Step-by-step explanation:

3. since the two triangles are similar, set up a proportion:

x+8/3x-9=24/28

*cross multiply*:

28(x+8)=24(3x-9)

28x+224=72x-216

44x=440

x=20

to find PR:

PR=3x-9

PR=3(20)-9

PR=51

4. same here:

39/4x+2=42/5x-2

39(5x-2)=42(4x+2)

195x-78=168x+84

27x=162

x=6

to find FE:

FE=5x-2

FE=5(6)-2

FE=28

6 0

2 years ago