SOLUTION: how do you find the y-intercept and the slope

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Question 77391: how do you find the y-intercept and the slope
Answer by checkley75(3666) About Me  (Show Source):
You can put this solution on YOUR website!
IF YOU HAVE THE STANDARD LINE EQUATION THEN YOU HAVE THE SLOPE(m) & THE Y INTERCEPT (b)
Y=mX+b
EXAMPLE
6=3X-4 HERE 3(m) IS THE SLOPE & -4(b) IS THE Y INTERCEPT.
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IF YOU HAVE 2 POINTS THUS (2,-4)(6+3) THEN YOU FIND THE SLOPE BY
(Y2-Y1)/(X2-X1)
(3+4)/(6-4)
7/2 IS THE SLOPE (m)
NOW SUBSTITUTE ONE SET OF X,Y VALUES & SOLE FOR THE Y INTERCEPT (b) THUS:
-4=7/2*2+b
-4=7+b
b=-4-7
b=-11 THIS IS THE Y INTERCEPT (b)
+graph%28+300%2C+200%2C+-6%2C+5%2C+-12%2C+12%2C+y+=+7x%2F2+-11%29+ (graph 300x200 pixels, x from -6 to 5, y from -12 to 12, y = 7x/2 -11).