Answer:
The expression to calculate the side BC is
Step-by-step explanation:
Notice that this is a problem of trigonometry in right triangles. So, the first step is to identify the data we have and the unknowns.
- The right angle is C.
- The measure of the angle B is .
- The length of the side AC is 7 in.
- We want to know the length of the side BC.
Then, the questions is: What trigonometrical functions relates the measure of an angle and the sides of a right triangle? The answer is: the tangent.
The formula for the tangent of B is opposite/adjacent; i.e.
Now, isolating the side BC
But the reciprocal function of the tangent is the cotangent, then
Finally, substituting the known values: