Answer:
27,0 the distance away from the school
Explanation:
Apply the formula for equation of a straight line;
y=mx+c where c is the y intercept , and m is the gradient
From the graph, the slope is negative where speed decreases with increase in time
Find the gradient by applying the formula;
![m=(y_2-y_1)/(x_2-x_1)](https://img.qammunity.org/2020/formulas/mathematics/high-school/pj0y5tg37a7a9ase0auiwe687ez8iaw2vl.png)
Taking y₁=24, y₂=20, x₁=9, x₂=12
Then;
![m=(20-24)/(12-9) =(-4)/(3)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/nt8ui2ksbyiufphsub9kgx9c796ks6o3fb.png)
write the equation of the function as ;
y=mx+c, c=36( the y-intercept when x=0) hence the equation is;
![y=mx+c\\\\y=(-4)/(3)x+36](https://img.qammunity.org/2020/formulas/mathematics/middle-school/1sko8nz7hfmh68hyobgkwoxp7jycioxkrf.png)
To get x-intercept, substitute value of y with 0
![y=mx+c\\\\\\y=-(4)/(3) +36\\\\\\0=-(4)/(3) x+36\\\\(4)/(3)x =36\\\\\\4x=36*3\\\\\\x=108/4=27](https://img.qammunity.org/2020/formulas/mathematics/middle-school/jjtgxukp2c8hhlu8usv3ph0j7nqgn2tl2g.png)
This means that the x-intercept is 27 ,and this means you will require 27 minutes to cover the whole distance to the school.