Answer:
![y=15x](https://img.qammunity.org/2020/formulas/mathematics/middle-school/iwoeimg3mk6288ns7fvzuu3paonval5f72.png)
Explanation:
Let
x ----> the time
y ----> the distance
we have the points
![(1,15),(2,30),(4,60),(6,90)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/y8kwpde38uvt97d6rwbghrffe55rp7tbdb.png)
Find the slope m
The formula to calculate the slope between two points is equal to
take the points
![(1,15),(6,90)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/28ncb7lppzyvenyd3jmkeuhoj6u26ru01n.png)
substitute in the formula
Find the linear equation in point slope form
![y-y1=m(x-x1)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/38rsw060gekfjbf76g57jsb45ginj88wcy.png)
we have
![point\ (1,15)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/ovwpz0kpiq2hzeqs962i9llxjrg1r751h3.png)
substitute
---> equation in point slope form
Convert to slope intercept form
![y-15=15x-15](https://img.qammunity.org/2020/formulas/mathematics/middle-school/xuthtogp5dfrtwjit8whda0l6lctj14n45.png)
![y=15x-15+15](https://img.qammunity.org/2020/formulas/mathematics/middle-school/dfflc10eerdgl3ocrgvevsssb81j7ra7lq.png)
![y=15x](https://img.qammunity.org/2020/formulas/mathematics/middle-school/iwoeimg3mk6288ns7fvzuu3paonval5f72.png)
Verify for x=2
----> is ok in the table
Verify for x=4
----> is ok in the table