1.2 Linearity and Intercepts Practice Example 1 Determine whether each function is a linear function. Justify your answer. 1. y = 3x 2. y = -2 +5x 3. 2x + y = 10 4. y = 4x Example 2 Determine whether each graph represents a linear or nonlinear function. 5 . 6. of 7. 8. Example 3 9. MEASUREMENT The table shows a function modeling the number of inches and feet. Can the relationship be modeled by a linear or nonlinear function? Explain. Inches 4 O 2 Feet 12 24 36 48 10. ASTRONOMY The table shows the velocity of Cassini 2 space probe as it passes Saturn. Is the velocity modeled by a linear or nonlinear function? Explain. Cassini 2 Velocity Time (s) 5 10 15 20 25 Velocity (mph) 50,000 60,000 70,000 60,000 50,000