Functions — Quiz 1

Questions in this quiz (8)

1. The graph of $$y=mx+b$$ is shown below in the $$xy$$-plane, where $$m$$ and $$b$$ are constants. What is the value of $$b$$?

   • 1
   • 2
   • 3
   • 4

2. For all $$t$$ > $$0$$, $$g(t) = \frac{1}{t}$$. Which of the following is true about $$g(t)$$?

   • It increases in proportion to $$t$$.
   • It decreases in proportion to $$t$$.
   • It decreases in proportion to $$t^2$$.
   • None of the above.

3. If $$f(x)=-3x^3+5x^2-4x+6$$, then find $$f(-2)$$.

   • -20
   • 68
   • 58
   • 36

4. A plumbing repair specialist charges a flat fee of 250 dollars for the first 3 hours of service, plus an hourly rate for each additional hour of service. The total cost for 7 hours of service is 450 dollars. Which function $$f(x)$$ gives the total cost, in dollars, for $$x$$ hours of service, where $$x \geq 3$$?

   • $$f(x) = 20x + 50$$
   • $$f(x) = -50x + 100$$
   • $$f(x) = 50x + 100$$
   • $$f(x) = 50x - 100$$

5. $$f(x)=4x+m$$In the above function, when $$x=3$$, $$f(x)=10$$. What is the value of the constant $$m$$?

   • 3
   • -2
   • 10
   • 4

6. The table gives values of the function $$f(x)$$:Which of the following functions defines the function $$f(x)$$ based on the values in the table?

   • $$x-4$$
   • $$2x$$
   • $$2x-4$$
   • $$x+4$$

7. Given: $$f(x) = 2x - 5$$ and the following values for $$g(x)$$. Find the value of $$f(g(3))$$.

   • 11
   • 12
   • 8
   • 6

8. The temperature in degrees Fahrenheit of a cup of coffee is modeled by the function $$T(t) = 180 - 5t$$ where $$T$$ is the temperature after $$t$$ minutes.What does the number 5 represent in the function?

   • The temperature of the coffee at time $$t$$
   • The initial temperature of the coffee
   • How much the temperature of the coffee decreases each minute
   • The time it takes for the coffee to reach room temperature