Question

What are the intercepts of this function? f(x) = -8x + 4 The x-intercept is (2,0), and the y-intercept is (0,4). The x-intercept is (-2,0), and the y-intercept is (0,-4). The x-intercept is (-3,0), and the y-intercept is (0,–4). The x-intercept is (0,0), and the y-intercept is (0,4).

Answer 1

Let the function y = f(x) = - 8x + 4

To find y-intercept:

Step1: Make y the subject of the formula.

Step2: The constant of the equation obtained in step 1, is the y-intercept

`\begin{gathered} y\text{ =f(x) = -8x+4} \\ y=\text{ -8x + 4} \\ \text{The y- intercept is 4} \end{gathered}`

Similarly, ( using the same steps), we can find x-intercept:

`\begin{gathered} y=-8x+4 \\ M\text{aking x the subject of formula, we get} \\ 8x=4-y \\ \text{Divide both sides by 8, we get} \\ x=(4-y)/(8) \\ x=(4)/(8)-(y)/(8) \\ x=-(y)/(8)+(1)/(2) \\ \text{The x-intercept is }(1)/(2) \end{gathered}`

The correct answers are: y-intercept is 4, while x-intercept is 1/2