Algebra!!!!!???? i neead help.?

Question

how do u use the forula y=Mx+b

Answer 1

that is the straight line formula.

M is the slope of the line

b is the point where the line intersects the y axis

x and y are variables -- plug in a x or y and solve for the other.

Answer 2

y = mx + b is called the point slope form for an equation of a line.
where m is slope, b is the y-intercept, x is the independant variable, and y is the dependant variable.

so for example:
if we were asked to find an equation of a line that passed through points A(1,2) and B(-1, -2)
first calculate the slope (rise/run)
starting at point B: y = -2 and goes to 2 at point A
so a total rise of 4
starting at point B again: x = -1, and goes to 1 at point A
total run = 2
so slope m = rise/run = 4/2 = 2

we now have y = 2x + b for our equation
now we need to solve for b. simply plug in the numbers from one of the points: take point A(1,2)
y = m(x) + b
2 = 2(1) + b
b = 2 - 2 = 0
in this case our b = 0 so our equation is
y = 2x + 0 or just y = 2x

another quick one: points: A(3, 4), B(7,11)
find the equation of the line
m = (11 - 4)/(7-3) = 7/4
y = (7/4)x + b
4 = (7/4)(3) + b
b = -5/4
now....
y = (7/4)x - (5/4)
(I wish this answers program had a drawing board or something)

Answer 3

M is the slope of the line rise(y direction) over run(x direction)
slope of 2 is 2 up and 1 right
b is a constant where the line crosses the y axis
use it to find a point on a line
for example
y=2x+1
if x=1 then y=3
x=2 then y=5
x=3 then y=7

Answer 4

any equation with that form graphs as a straight line. if you have 2 points, say (1,3) and (5,-4), then you can get the equation of the line in 2 steps:

find the slope by subtracting y coordinates, -4 - 3 = -7, subtracting x coordinates, 5 - 1 = 4, and making a fraction, change in y over change in x, -7/4, called the slope.

so far we know the equation is y = (-7/4)x + b. to get b, we plug in one of the points:

3 = (-7/4)(1) + b
4/4 + 7/4 = b
b = 11/4

so we have y = (-7/4)x + 11/4 as the equation of the line through our 2 points.

Answer 5

y = the y coordinate of the point on a line

m = the slope of the line

x = the x coordinate of the point on a line

b = the y intercept (which point on the y axis the line crosses)

If you have 3 of the above pieces of information, you can solve for the 4th one.

Answer 6

m is the slope.. which is found by change in y over change in x
use any (x,y) point and substitute that in as x and y if you are trying to find "b".
b is the y-intercept.. when x equals 0 and y equals something (b).

Answer 7

take whatever number M is, multiply that number by whatever x is, add whatever b is to that number, then what you've got is y.