Answer:
Step-by-step explanation:
Slope m is defined as m=(y2-y1)/(x2-x1) in this case
m=(218-155)/(22-15)=63/7=9
y=mx+b
y=9x+b, using point (15,155) we can solve for the y intercept b
155=9(15)+b
155=135+b, b=20 so the line is
y=9x+20
In thirty days there will be
y=9(30)+20=290 coins
