so points are (x,y) (50,1.55) (100,2.25) (150,2.95) (20,3.65)
so solve for slope/m you do (y₁-y₂)/(x₁-x₂) so just use any for example (1.55-2.25)/(50-100)=-0.70/-50=1 times 0.7/50=7/500= (to convet to decimal form) 14/1000=1.4/100=0.14/10=0.014/1=0.014
slpoe is 0.014
y=0.014x+b
input one of the points exg 50 for x and 1.55 for y and solve for b 1.55=0.014(50)+b 1.55=.7+b subtract .7 from both sides 0.85=b