Question

Solving a right triangle (ROUND TO THE NEAREST TENTH)

Answer 1

see explanation

Explanation:

The sum of the 3 angles in a triangle = 180°

Subtract the sum of the given angles from 180 for B

B = 180° - (90 + 40)° = 180° - 130° = 150°

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sin40° =
`(opposite)/(hypotenuse)` =
`(a)/(21)`

Multiply both sides by 21

21 × sin40° = a, thus

a ≈ 13.5 ( to the nearest tenth )

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cos40° =
`(adjacent)/(hypotenuse)` =
`(b)/(21)`

Multiply both sides by 21

21 × cos40° = b, thus

b ≈ 16.1 ( to the nearest tenth )