每日一题

Mathematics>Standard Multiple Choice

Read the following SAT test question and then click on a button to select your answer.

If the graph of the function f is a line with slope 2, which of the following could be the equation of f?

(A)f(x)= 4x-2
(B)f(x)= 2x+ 4
(C)f(x)= -(2x)-2
(D)f(x)= (1/2)x + 2
(E)f(x)= -((1/2)x) + 1/2

答案和解析

答案：B

解析：

The graphs of all the given functions are lines, and the equations are all in the form y = (mx) + b. When a linear equation is in the form y = (mx) + b, the slope of the graph of the equation is m , the coefficient of x. The graph of the function f is a line with slope 2, so the only choice that could be the equation of f is function f of x = (2x) + 4.