Plug in the values from the chart! Use the pair (-3, -7) from the top of the chart and eliminate answers that are not true: (A) becomes -7 = -3 – 4, which is true. Keep it. Keep (B): -7 = 2(-3) – 1 is true. Get rid of (C), which becomes -7 = 2(-3) + 2: -7 does not equal -4. Get rid of (D): -7 = 3(-3) – 3. -7 does not equal -12. Now use another pair just to test (A) and (B). Using (-1, -3), (A) gives -3 = -1 – 4, which is not true, so eliminate it, leaving only (B). The values (-1, -3) work: -3 = 2(-1) – 1.

To find the value of f(3) + f(5), find the values of f(3) and f(5) separately: f(3) = 2(3)2 + 4 = 22 and f(5) = 2(5)2 + 4 = 54. So f(3) + f(5) = 76. You can tell that f(4) will be between 22 and 54, so you can cross out (A). If you ballpark (C) and (D), putting 10 or 15 in the function will give you a number bigger than 100, and you’re looking for 76, so (C) and (D) are too big. That means the answer is (B) by POE.

Figure out the points that will be on the graph from the data given: (0, 0), (1, 5), (2, 10), (3, 15), (4, 20). Draw a line through or close to these points to get an idea of what the graph will look like. Then use POE. The line is linear, not quadratic, so you can eliminate (D). It is also clear that the line begins at the origin, so the y-intercept will be 0. This will eliminate (A). A slope of 25 is far too big-ballpark-so you can eliminate (B), leaving (C).