Calculate the value of a to one decimal place

Okay, you will need to use the law of cosines for this problem.

The Law of Cosines states (in this case): a^2 = b^2 + c^2 - 2 * b * c * cos A, where "a" is the side opposite angle A (7 inches), and b and c are the other two sides.

Plug the numbers in and you get: 7^2 = 5^2 + 9^2 - 2 * 5 * 9 * cos A, or:

49 = 25 + 81 - 90 * cos A.

Subtract (25 + 81) from both sides to get:

-57 = -90 * cos A.

Divide by -90 on both sides:

cos A = 19/30

To find A, you do the inverse trigonometric function to get:

cos^-1 of (19/30) = A.

I don't have a calculator that can do this right now, but if you plug the left side of the above equation into it (make sure it is in degrees, not radians), you should get A.

Value of A is 50.7°

Step-by-step explanation:

Given: All sides of triangle.

let, a = 7 in.  , b = 5 in.   and    c = 9 in.

We have to find Value of A that is measure of Angle A.

Figure is attached.

We use law of cosines.

The law of cosines is used for calculating one side of a triangle when the angle opposite and the other two sides are known.

a² = b² + c² - 2bc × cos A

⇒ 7² = 5² + 9² - 2 × 5 × 9 × cos A

49 = 25 + 81 - 90 × cos A

49 - 106 = -90 × cos A

-57 = -90 × cos A

cos A =

A =

A = 50.7°

Therefore, Value of A is 50.7°

square root of 36/6 = 2.449489743

square root of 16/6 = 1.632993162

square root of 6 = 2.449489743

the answer is square root of 16/6 because the square root of 36/6 is the same answer as square root of 6 = 2.449489743

answer: it's d

step-by-step explanation: