Question

4/r = cos 43

topic trigonometry

Answer 1

The value of the variable r is 5. 48

To determine the value of the variable, r, we need to know that trigonometric identities are equations involving trigonometric functions that are true for all values of the variables.

The different trigonometric identities are;

• sine
• cosine
• tangent
• cotangent
• secant
• cosecant

From the information given, we have that the equation is;

4/r = cos 43

cross multiply the values

r = 4/cos 43

find the value of the identity

r = 4/0.73

divide the values

r = 5. 48

Answer 2

r ≈ 4.35

Explanation:

given

`(4)/(r)` = cos43° ( multiply both sides by r to clear the fraction )

4 ×
`(4)/(r)` = r × cos43° ( simplify both sides )

4 = rcos43° ( isolate r by dividing both sides by cos43° )

`(4)/(cos43)` = r , that is

4.35 ≈ r ( to 2 decimal places )