Acute angle *B* has *n* degrees. Consider this statement: “If angle *B* is subtracted from its supplement, then the result is twice the complement of angle *B*.”

- Give
*n*several values, then see whether you think the sentence is true. - Show algebraically that the statement is true or not true.

If you try a few examples, you’ll soon believe the statement is true. Let’s try a general argument.

Let *S* be the supplement of *B* and *C* be the complement. Then:

*S – B* = (180 – *B*) – *B* = 180 – 2*B* = 2(90 – *B*) = 2*C*.