SOLUTION: How do you find the slope and y intersept on a graph? (this is 8th grade math)

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Question 158639: How do you find the slope and y intersept on a graph? (this is 8th grade math)
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
SORRY THAT I AM NOT USING THE SAME APPROACH BUT THIS IS HOW I WAS TAUGHT & HOW IT IS TAUGHT IN OUR LOCAL SCHOOLS WHERE I HAVE TAUGHT.
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GIVEN TWO POINTS (1,4) & (-2,6)
SLOPE=(Y2-Y1)/(X2-X1)
SLOPE=(6-4)/(-2-1)
SLOPE=2/-3=-2/3
NOW REPLACE THE X & Y TERMS IN THE LINE EQUATION [Y=mX+b] WITH ONE SET OF (X,Y) VALUES. m=SLOPE & b=Y INTERCEPT.
NOW SOLVE FOR b.
4=(-2/3)1+b
4=-2/3+B
b=4+2/3
b=(12+2)/3=14/3 IS THE Y INTERCEPT.
Y=-2X/3+14/3
+graph%28+300%2C+200%2C+-6%2C+8%2C+-10%2C+10%2C+-2x%2F3+%2B14%2F3%29+ (graph 300x200 pixels, x from -6 to 8, y from -10 to 10, -2x/3 +14/3).