Question

What is the y-intercept of the line given by the equation y=9/2x - 4?

Answer 1

`-4`

Explanation:

Given equation: `y=9/2x-4`
The given equation of the line is in slope-intercept form. The general slope-intercept form would be:
`y=mx+b` where `m` is the slope and `b` is the y-intercept of the line

Therefore, the slope of the given equation is `9/2` and the y-intercept is `-4`.

Answer 2

(0,-4)

Explanation:

graph{9/2x-4 [-4.98, 5.02, -4.76, 0.24]}

Method 1

The graph of `y=9/2x-4` is shown above.

From the graph, it is shown that the coordinates of the y-intercept is `(0,-4)`. Although this is not needed, the coordinates of the x-intercept is `(8/9,0)`.

Method 2

From the above coordinates, you can see that at the y-intercept, the value of `x=0`. Conversely, at the x-intercept, the value of `y=0`.

Thus, when `x=0`,
`y=(9/4)*0-4`
`y=-4`
`:.` y-intercept is `(0,-4)`

Be careful of leaving your answer simply as `y=-4`.

The correct form of answering should be leaving it as (0,-4).