Question

Calculate the value of angle A to one decimal place. Picture Attached

Answer 1

`A = 50.7` (to nearest tenth)

Explanation:

Use the Law of Cosines to find the value of angle A as follows:

`cos(A) = (b^2 + c^2 - a^2)/(2*b*c)`

Where,

a = 7 in

b = 5 in

c = 9 in

Plug in the values into the formula

`cos(A) = (5^2 + 9^2 - 7^2)/(2*5*9)`

`cos(A) = (57)/(90)`

`cos(A) = 0.6333`

`A = cos^(-1)(0.6333)`

`A = 50.7` (to nearest tenth)