Answer:
3. y = 3.5x + 1.5
4. y = -6x - 56
Step-by-step explanation:
3. When you write functions, you know that the base equation is y = mx+b. In this problem, you automatically see the b (y-intercept) so that can be filled in right away. y = mx + 1.5. Now, see how much the y is growing for every 100, and divide that by 100 to get how much it is growing by every 1. 36.5-1.5 = 35. 35/100 = 3.5. Now we see that the slope is 3.5, and your equation is done.
y = 3.5x + 1.5
4. For this one, it is decreasing, so the base equation must have a negative slope. y = -mx + b. For every 10, it is decreasing by 6, so the slope is -6. y = -6x + b. Now, a trick that you can use for finding the y intercept is to plug in one of the coordinates from the table and work it out that way.
Ex: 94 = -6(25) +b (multiply -6 by 25)
94 = -150 + b (add 150 to each side)
b = -56. Your full equation is y = -6x -56
