SOLUTION: how do you find the b in y=mx+b

Algebra.Com
Question 238193: how do you find the b in y=mx+b
Answer by Theo(13342)   (Show Source): You can put this solution on YOUR website!
the standard form is y = mx + b where m is the slope and b is the y-intercept.

assume you are given the slope and one point on the line.

let the slope = 2

let the point = (3,5)

the standard form of y = mx + b becomes y = 2x + b

now you take the point (x,y) = (3,5) that is on the line (has to be on the line) and replace x and y in the equation with it.

the equation becomes 5 = 2*3 + b

then you solve for b.

in this case b = 5-1 = -1

your equation becomes y = 2x - 1

graph of that equation looks like:



b is the y intercept which is the value of y when x = 0 which is -1.

the graph confirms that.

the slope is 2 which means that everytime x increases 1 unit, y increases 2 units.

that can be seen on the graph as well.

when x = 0, y = -1.

when x = 1, y = 1

when = 2, y = 3

etc.


RELATED QUESTIONS

How do you find the answers to y=mx+b. I just dont understand. Please... (answered by wuwei96815)
In the equation y = mx + b: if you know the slope, how do you solve for the y... (answered by checkley77)
how do you write in slope form y=mx+b and whats the slope?... (answered by doukungfoo)
i need 7y+6x=10 in y=mx+b form? How do you do... (answered by tutorcecilia)
Using the formula mx+b=y; how do you determine b? (answered by richwmiller)
Find the equation of each line in y=mx+b form. (3,2) undefined slope how do i do this? (answered by checkley77)
How do you write 3x = y + 4 in y = mx + b... (answered by stanbon)
how do you graph a y=mx+b... (answered by josgarithmetic)
HOW DO YOU SOLVE 4x-6y=18 AND PUT IT IN y=mx+b... (answered by drj)