Slope Intercept form
y = mx + b
-1 = 2(4) + b
-1 = 8 + b
- 1 - 8 = 8 + b - 8
- 9 = b
- - - - - - -
The equation
y = 2x - 9
- - - - - - - -s-
2007-06-05 07:48:56
·
answer #1
·
answered by SAMUEL D 7
·
1⤊
0⤋
There are two ways to do this problem. The first is to make a graph and plot the point (4,-1) and then give it a slope of 2. The second is to solve it algebraically
Since I very well can't show you a graph, ill show you how to do it the algebraic way.
The equation for a line will be in the form y=mx+b
m= slope
b=y intercept (what y equals when x=0)
Since you have already been provided with a slope, you can put it into the equation quickly.
y=2x+b
Now we just need the b, which isnt that hard to find. To find b, plug the point (4,-1) you were given into the equation. Replace the y with -1 since -1 is the y value. Replace x with 4.
Now you have:
-1=2(4)+b
now you can solve for "b"
b=-9
so you get the equation y=2x-9
2007-06-05 07:52:10
·
answer #2
·
answered by underdog 2
·
0⤊
0⤋
To start, you need the point-slope formula,
y - y1 = m(x - x1)
*The ones are subscripts.
The ordered pair represents those x1 and y1 values, and m is your slope... so if you plug them into the formula,
y - (-1) = 2(x - 4)
y + 1 = 2x - 8
y = 2x - 9
...This is your linear function (since x is raised to only a power of 1).
2007-06-05 07:48:21
·
answer #3
·
answered by mattside_bic 2
·
0⤊
0⤋
3.) m = 3/4 x = - 3 y = a million b = y - mx ........ (Derived from y = mx + b) b = a million - 3/4(- 3) b = a million - 9/4 b = 4/4 - 9/4 b = - 5/4 Equation: y = 3/4 x - 5/4 ¯¯¯¯¯¯¯¯¯¯¯¯ 4.) x1 = - a million y1 = - 2 x2 = a million y2 = - 10 m = (y2 - y1) / (x2 - x1) m = [- 10 - (- 2)] / [a million - (- a million)] m = (- 10 + 2) / (a million + a million) m = - 8/2 m = - 4 b = y1 - m(x1) b = - 2 - [- 4(- a million)] b = - 2 - 4 b = - 6 Equation: y = - 4x - 6 ¯¯¯¯¯¯¯¯¯¯
2016-11-05 00:35:54
·
answer #4
·
answered by Anonymous
·
0⤊
0⤋
slope = (y2 - y1)/(x2 - x1)
2 = (y - (-1))/(x - 4)
2 = (y + 1) / (x - 4)
2(x - 4) = y + 1
y = 2x - 9
2007-06-05 07:51:34
·
answer #5
·
answered by topsyk 3
·
0⤊
0⤋
F(X)= 2X + C
- 1 = 2(4) + C , C= -9
F(X)= 2X - 9
2007-06-05 07:45:48
·
answer #6
·
answered by pioneers 5
·
0⤊
0⤋