URGENT
If 90°≤A≤180° and sin(A) = 4/7, then determine the exact values of cos(A) and tan(A).

If A is between the angles 90° and 180°, and we know that:

Sin(A) = 4/7.

But here we have an obvious problem, in the second quadrant, Sin(X) can only have negative values, and we know that 4/7 is a positive number

This means that the actual value of A is not a real value.

If we use the relation:

Asin(Sin(A)) = A = Asin(4/7) = 37°

We would find that A must be smaller than 90°.

And for the periodicity of the trigonometric functions, the next possible value for A will be 37° + 360° = 397°, that is bigger than 180°

And as the Value of A does not exist, the same happens for Cos(A) and tan(A)

c is the answer

step-by-step explanation:

answer:   28.56 feet (approx)

step-by-step explanation:

since, triangle abc has measure of angle c equal to 55 degrees, measure of angle abc equal to 90 degrees, and length of bc equal to 20 feet.

we have to find out the measurement of segment ab.

therefore, tan 55° =

but bc = 20 feet.

⇒ tan 55 ° =  

⇒ ab = 20 × tan 55 °

⇒ ab = 20 × 1.42814800674

⇒ ab = 28.5629601348   ≈ 28.56 feet