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How would I figure out a linear equation with two plot points with fractions? (1/3(6),3) and (1/2(19),-2) are my two plot points. I was able to graph them on Desmos, but I can't seem to figure out how I would go about figuring out the slope and y-intercept in this case... the fractions are what's throwing me off here. Please help!

User Darrielle
by
8.7k points

1 Answer

3 votes

Answer:
m=(-30)/(79),\ y=5.40

Explanation:

Given

Points are
\left(6(1)/(3),3\right),\ \left(19(1)/(2),-2\right)

Convert mixed numeral to fraction


\left(6(1)/(3),3\right)\Rightarrow \left((19)/(3),3\right)\\\\\left(19(1)/(2),-2\right)\Rightarrow \left((39)/(2),-2\right)

Slope of the line is


\Rightarrow m=(3-(-2))/((19)/(3)-(39)/(2))\\\\\Rightarrow m=(5)/((38-117)/(6))\\\\\Rightarrow m=(-30)/(79)

Equation of line


\Rightarrow (y-3)/(x-(19)/(3))=(-30)/(79)\\\\\text{for y-intercept, put x=0}\\\\\Rightarrow (y-3)/(0-(19)/(3))=(-30)/(79)\\\\\Rightarrow y-3=(190)/(79)\\\\\Rightarrow y=3+2.40\\\Rightarrow y=5.40

User Pkerckhove
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8.3k points