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Use f(x)=(1)/(2x+9) and g(x)=3x² -44 to evaluate the following. (f-9)(-4)

User Kevin Brey
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Final answer:

To evaluate the expression (f-9)(-4), calculate f(-4) using f(x) = ⅛(2x+9), which equals ½, then subtract 9 to get the final result, -₈½.

Step-by-step explanation:

To evaluate the expression (f-9)(-4), we first need to find the value of the function f at x = -4 and then subtract 9 from the result.

Using the given function f(x) = ⅛(2x+9), we substitute x with -4:

f(-4) = ⅛(2(-4)+9) = ⅛(-8+9) = ⅛

Now, we compute the value:

f(-4) = ⅛(1) = ½

Next, we subtract 9 from the computed value of f(-4):

(f-9)(-4) = f(-4) - 9 = ½ - 9

Finally, we get the result:

(f-9)(-4) = -₈½