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Richay
06-11-2006, 06:17 PM
I need tor refresh my mind on this.

Find the y-intercept of a line going through (3, 0) and having a slope of -5

What are my steps?

y=mx+b

y = -5(x=0?) + b

What do I need to do.

skeeter
06-11-2006, 06:26 PM
for this specific question, LOOK at the coordinates of the given point.

if it were another point, find the linear equation using the point-slope form ... then set y = 0 and solve for x.

jonboy
06-11-2006, 09:28 PM
I need tor refresh my mind on this.

Find the y-intercept of a line going through (3, 0) and having a slope of -5

What are my steps?

y=mx+b

y = -5(x=0?) + b

What do I need to do.

Ok you would definetly use slope intercept form.

Formula needed: y=mx+b
Definition of Slope Intercept equation: m=slope, b=y-intercept
Fill in your known info: y=-5x+b

Whenever you are trying to solve for the y-intercept, and
you know m(slope) then you fill a the coordinate you know

So: 0=-5(3)+b

Solve for b and fill the known info again and you got your equation. :)

Richay
06-12-2006, 08:53 PM
0=-5(3)+b

-5 x 3 = -15

-15 + 15 = 0

K I see, thank you!