Q:

How do you do 21 and 22?

Accepted Solution

A:
Answer:   21.  d.  39   22.  c.  20; 7Step-by-step explanation:21. This is straightforward evaluation of the function. Put the numbers 8 and -5 where x is in the function definition and do the arithmetic. Then find the difference of the results.   f(8) = 3·8 -2 = 22   f(-5) = 3·(-5) -2 = -17   f(8) - f(-5) = 22 - (-17) = 22 +17 = 39__22. The first part is similar to 21—evaluate the function for x=2.   f(2) = 24 -2·2 = 24 -4   f(2) = 20Note that this result is sufficient to allow you to choose the correct answer.However, we can also do the second part. Find x for f(x) = 10   f(x) = 24 -2x   10 = 24 - 2x . . . . . . substitute 10 for f(x)   -14 = -2x . . . . . . . . . subtract 24 from both sides   7 = x . . . . . . . . . . . . . divide both sides by -2