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Please save my life

Please save my life-example-1
User Koola
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2 Answers

7 votes

Answer:

by using Pythagoras law

ac²=ab²+bc²

20²=ab²+8²

ab²=20²-8²

AB=√336=18.33

Explanation:

sin a=p/h=8/20=2/5

cos a =b/h=18.33/20

tana =p/b=8/18.33

User Shlublu
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4.3k points
11 votes

We are Given:_______________________________________________

ΔABC right angled at B

BC = 8

AC = 20

Part A:_____________________________________________________

Finding the length of AB

From the Pythagoras theorem, we know that:

AC² = BC² + AB²

replacing the given values

(20)² = (8)² + AB²

400 = 64 + AB²

AB² = 336 [subtracting 64 from both sides]

AB = 18.3 [taking the square root of both sides]

Part B:_____________________________________________________

Finding Sin(A)

we know that Sin(θ) = Opposite / Hypotenuse

The side opposite to ∠A is BC and The hypotenuse is AC

So, Sin(A) = BC / AC

Sin(A) = 8/20 [plugging the values]

Sin(A) = 2/5

Part C:_____________________________________________________

Finding Cos(A)

We know that Cos(θ) = Adjacent / Hypotenuse

The Side adjacent to ∠A is AB and the hypotenuse is AC

So, Cos(A) = AB / AC

Cos(A) = 18.3/20 [plugging the values]

Cos(A) = 183 / 200

Part D:_____________________________________________________

Finding Tan(A)

We know that Tan(θ) = Opposite / Adjacent

Since BC is opposite and AB is adjacent to ∠A

Tan(A) = BC / AB

Tan(A) = 8 / 18.3 [plugging the values]

Tan(A) = 80 / 183

User Kbcool
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4.4k points