If f(x) = 2x + 5, what is f(4) − f(1)?
f(4) = 2(4) + 5 = 13 and f(1) = 2(1) + 5 = 7, so the difference is 6. Shortcut: for a linear function the constant cancels, leaving 2 × (4 − 1) = 6.
Digital SAT practice test
Questions 9 and 10 of 10
In "her argument was cogent", cogent most nearly means:
Cogent means clear and persuasive. It describes the quality of the reasoning, not its length or tone.