How do you find a variable?

A symbol for a value we don't know yet. It is usually a letter like x or y. Example: in x + 2 = 6, x is the variable.

Law of sines can be used to find the value of q.

Step-by-step explanation:

∠P, ∠Q and ∠R is given.

p is also given, we need to find the value of q.

To use law of cosines, we must have at least 2 values, that is p and r but here we have only p value, so we can use the law of sines which was given as,

sin P/p = sin Q/ q = sin R / r

So using the first 2 ratios, we can find q as,

sin P/p = sin Q/ q

Rewriting the equation for q as,

q = p × sin Q / sin P

we will get the value of q.