General equation of line is:
[tex]y=mx+c[/tex](a)
Where c represent y intercept then the value of c is zero.
so equation is:
[tex]y=mx[/tex]Where m represent the slope.
[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]Pick two point from graph .
[tex]\begin{gathered} (20,10) \\ (10,5) \end{gathered}[/tex][tex]\begin{gathered} m=\frac{10-5}{20-10} \\ m=\frac{5}{10} \\ m=\frac{1}{2} \end{gathered}[/tex]So
[tex]y=\frac{1}{2}x[/tex]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:
[tex](30,15)[/tex](b)
Lebel the axes is
[tex]y=x[/tex]That mean value of y is double .
