7-6a Write Equations

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More Information

First of all.  You are MUCH smarter than this program.
What you would normally write as:
y - 3x = 2
The equation maker might write as
-1y + -3x = 2
or occasionally as
-1y + -3x + 0 = 2
That's okay.  We know you're smart enough to ignore the superfluous information.

When you write an equation as y=mx+b then it is in slope-intercept form.
The number in front of the x is the slope and the b is the y-intercept (the y-value when x is 0)

For the slope= -4/3 and point (3,-1)

The formula is y=mx+b.
We know everything but b.
Plugging in the slope and the points we get
-1=-4/3(3)+b
Which is
-1=-4+b
Which means b=3
Thus the formula is y=-4/3x+3

For the point (8,5) and point (-8,-1)

The formula is find the slope and then do the same calculations as before with either point:
Slope is rise over run.
Rise is 5 - -1 or 6
Run is 8 - - 8 or 16
Slope is 6/16 or 3/8 or 0.375

Plugging the slope and the first point into our y=mx+b formula, we get
5=3/8(8)+b
which is
5=3+b
which means b=2 and our formula is
y=3/8x+2