Question

Find the value of the Cosine A B C D

Answer 1

The cosine for ∠A is $\frac{5\sqrt{89} }{89}$.

Option: A.

Step-by-step explanation:

From the given diagram,

Opposite = 8 ft.

Adjacent = 5 ft.

In trigonometry, the formula for cosine = $\frac{adjacent}{hypotenuse}$.

We are not given with hypotenuse. So we have to find the hypotenuse using Pythagorean Theorem $hypotenuse = \sqrt{opposite^2+adjacent^2}$

$hypotenuse = \sqrt{8^2+5^2}$.

$hypotenuse = \sqrt{64+25}$.

hypotenuse = $hypotenuse = \sqrt{89}$.

cosine = $\frac{5}{\sqrt{89} }$.

Multiply $\sqrt{89}$ in both numerator and denominator,

The cosine for ∠A is $\frac{5\sqrt{89} }{89}$.