Function Machines — Practice Problems and Worked Solutions

The formulas you need here

17 worked problems

Every step is generated and checked by a computer algebra system.

1. 1.

   Evaluate the function at the given input.

   $$f(x)=x+2,f(3)=?$$

   Answer: $5$

   Step-by-step solution

   1. $$\text{Replace every }x\text{ with }3.$$
   2. $$f(3)=5$$
2. 2.

   Evaluate the function at the given input.

   $$f(x)=2x+1,f(4)=?$$

   Answer: $9$

   Step-by-step solution

   1. $$\text{Replace every }x\text{ with }4.$$
   2. $$f(4)=9$$
3. 3.

   Evaluate the function at the given input.

   $$f(x)=3x-1,f(2)=?$$

   Answer: $5$

   Step-by-step solution

   1. $$\text{Replace every }x\text{ with }2.$$
   2. $$f(2)=5$$
4. 4.

   Evaluate the function at the given input.

   $$f(x)=5-x,f(3)=?$$

   Answer: $2$

   Step-by-step solution

   1. $$\text{Replace every }x\text{ with }3.$$
   2. $$f(3)=2$$
5. 5.

   Evaluate the function at the given input.

   $$f(x)=4x+2,f(-1)=?$$

   Answer: $-2$

   Step-by-step solution

   1. $$\text{Replace every }x\text{ with }-1.$$
   2. $$f(-1)=-2$$
6. 6.

   Evaluate the function at the given input.

   $$f(x)=3-2x,f(-2)=?$$

   Answer: $7$

   Step-by-step solution

   1. $$\text{Replace every }x\text{ with }-2.$$
   2. $$f(-2)=7$$
7. 7.

   Evaluate the function at the given input.

   $$f(x)=2x+5,f(1)=?$$

   Answer: $7$

   Step-by-step solution

   1. $$\text{Replace every }x\text{ with }1.$$
   2. $$f(1)=7$$
8. 8.

   Evaluate the function at the given input.

   $$f(x)=3x+2,f(4)=?$$

   Answer: $14$

   Step-by-step solution

   1. $$\text{Replace every }x\text{ with }4.$$
   2. $$f(4)=14$$
9. 9.

   Evaluate the function at the given input.

   $$f(x)=5x-2,f(3)=?$$

   Answer: $13$

   Step-by-step solution

   1. $$\text{Replace every }x\text{ with }3.$$
   2. $$f(3)=13$$
10. 10.

    Evaluate the function at the given input.

    $$f(x)=4-3x,f(2)=?$$

    Answer: $-2$

    Step-by-step solution

    1. $$\text{Replace every }x\text{ with }2.$$
    2. $$f(2)=-2$$
11. 11.

    Evaluate the function at the given input.

    $$f(x)=2x+7,f(-2)=?$$

    Answer: $3$

    Step-by-step solution

    1. $$\text{Replace every }x\text{ with }-2.$$
    2. $$f(-2)=3$$
12. 12.

    Evaluate the function at the given input.

    $$f(x)=4x-1,f(5)=?$$

    Answer: $19$

    Step-by-step solution

    1. $$\text{Replace every }x\text{ with }5.$$
    2. $$f(5)=19$$
13. 13.

    Evaluate the function at the given input.

    $$f(x)=x+6,f(8)=?$$

    Answer: $14$

    Step-by-step solution

    1. $$\text{Replace every }x\text{ with }8.$$
    2. $$f(8)=14$$
14. 14.

    Evaluate the function at the given input.

    $$f(x)=2-4x,f(1)=?$$

    Answer: $-2$

    Step-by-step solution

    1. $$\text{Replace every }x\text{ with }1.$$
    2. $$f(1)=-2$$
15. 15.

    Evaluate the function at the given input.

    $$f(x)=6x+3,f(2)=?$$

    Answer: $15$

    Step-by-step solution

    1. $$\text{Replace every }x\text{ with }2.$$
    2. $$f(2)=15$$
16. 16.

    Evaluate the function at the given input.

    $$f(x)=3x-5,f(4)=?$$

    Answer: $7$

    Step-by-step solution

    1. $$\text{Replace every }x\text{ with }4.$$
    2. $$f(4)=7$$
17. 17.

    Evaluate the function at the given input.

    $$f(x)=2x+4,f(6)=?$$

    Answer: $16$

    Step-by-step solution

    1. $$\text{Replace every }x\text{ with }6.$$
    2. $$f(6)=16$$

More from Math Foundations

• Order of Operations
• Signed Numbers
• Fraction Sense
• Ratios and Percentages
• Exponents and Roots
• Algebraic Expressions
• Linear Equations
• Polynomial Basics
• Inequalities
• Coordinate Plane
• Reading Graphs
• Substitution
• Factoring Basics