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3 years ago

Can anyone help me with trig identities?

Mathematics

1 answer:

nevsk [136]3 years ago

6 0

Answer:

cosA = √(21/25)

Step-by-step explanation:

We know

sin²(A) + cos²(A) = 1

Next, we know that sin(A) = 2/5. Plugging that into our equation, we get

(2/5)² + cos²A = 1

4/25 + cos²A = 1

subtract 4/25 from both sides to isolate cos²A

cos²A = 1 - 4/25 = 25/25-4/25 = 21/25

square root both sides to get

cosA = √(21/25)

We do not include -√(21/25) in our possible answer for cosA because this is in quadrant 1, so cosA must be positive.

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denpristay [2]

Answer:

y = (-6/13)x + (4/13).,

Step-by-step explanation:

the equation of the line is:

y = mx + b, where "m" is the slope and "b" gives the y-intercept

m = (y2 - y1)/(x2 - x1)

m = (-2 - 4)/(5 - (-8))

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4 = (-6/13)(-8) + b

b = 4 - (-6/13)(-8)

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the equation of the line that passes through the points (-8,4) and (5,-2) is:

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3 years ago

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dusya [7]

Answer:

See explanation

Step-by-step explanation:

The question is incomplete, as the diagram of coordinates of the three triangles are not given.

A general explanation is as follows:

First, record the coordinates of the corresponding points of the three triangles.

For instance; In triangles ABC, DEF and GHI; A, D and G are corresponding points.

Now, assume the coordinates are:

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Point D is 4 points to the right of A;

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Answer:

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Step-by-step explanation:

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3 years ago

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