When the sun was directly overhead, the stick had no shadow. After 20 minutes, the shadow was 10.5 cm long. After 60 minutes, it was 26 cm long.

Based on this information, estimate how long it will be after 95 minutes?

Example:
y=mx+b is the slope intercept form where m is the slope and b is the y intercept 
so get y on one aside and everything else on the other by subtracting and dividing.
2x+3y=9
3y=-2x+9
y=-2x/3+9/3
y=-2/3*x+3    3x-x+2=4 so the equation to the example is 4