Answers:
cos(A) = 0.8480
tan(B) = 1.6
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Step-by-step explanation:
Before we can compute cos(A), we'll need to find the hypotenuse.
Use the pythagorean theorem.
a^2 + b^2 = c^2
8^2 + 5^2 = c^2
89 = c^2
c^2 = 89
c = sqrt(89)
The hypotenuse is exactly sqrt(89) units long.
This will allow us to find the cos(A) value
cos(angle) = adjacent/hypotenuse
cos(A) = AC/AB
cos(A) = 8/sqrt(89)
cos(A) = 0.84799830400509 which is approximate
cos(A) = 0.8480 when rounding to four decimal places
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For the tangent ratio, we won't use the hypotenuse. Instead, we use the opposite and adjacent sides like so:
tan(angle) = opposite/adjacent
tan(B) = AC/BC
tan(B) = 8/5
tan(B) = 1.6