Question

4) Here is a graph that represents a proportional relationship. a

Answer 1

General equation of line is:

`y=mx+c`

(a)

Where c represent y intercept then the value of c is zero.

so equation is:

`y=mx`

Where m represent the slope.

`m=(y_2-y_1)/(x_2-x_1)`

Pick two point from graph .

`\begin{gathered} (20,10) \\ (10,5) \end{gathered}`
`\begin{gathered} m=(10-5)/(20-10) \\ m=(5)/(10) \\ m=(1)/(2) \end{gathered}`

So

`y=(1)/(2)x`

this equation represent this graph.

(c)

The equation of line is straight line so graph title is straight line.

(d)

At x=30 then the coordinates of graph is:

`(30,15)`

(b)

Lebel the axes is

`y=x`

That mean value of y is double .