for january we have points (1,10) and (31,12)
for february we have points (1,12) and (28,9)
for march we have points (1,9) and (31,15)
slope (m) = (y2-y1)/(x2-x1)
slope of january = (12-10)/(31-1) = 2/30 =1/15
slope of febraury = (9-12)/(28-1) = -3/27 = -1/9
slope of march = (15-9)/(31-1) = 6/30 =1/5
equation of line for january is y=(x/15)+b
use first january point
10=(1/15)+b , b=9.93
january line formula y = (x/15)+9.93
equation of line for february is y=(-x/9)+b
use first february point
12=(-1/9)+b , b =12.11
february line formula y=(-x/9)+12.11
equation of line for march is y=(x/5)+b
9=(1/5)+b , b= 8.8
march line formula y = (x/5)+8.8
now graph for these three line is
red line for january
blue line for february
green line for march
Comments
Dear Eric, thank you for correcting us. A mistake was fixed.
Why are you using 10 here instead of 9? 10=(1/5)+b , b= 9.8. for March
Leave a comment