Question

find a linear function with slope -3 that contain (-1,4) graph the function

Answer 1

You've got \[(x,y)=(-1,4)\]
And the linear function:
\[f(x)=a\cdot x+b\]
Find b:
\[f(-1)=-3\cdot -1+b\]

Answer 2

\[f(-1)=4\] of course

Answer 3

When you've found b, you just insert a and b into the linear function and let x be your variable.

Answer 4

you could use the equation
m=(y-y1)/(x-x1)
m would be the slope of your function
y1 the y component of the coordinate
and x1 the x component of the coordinate
therefore,
-3=(y-4)/(x-(-1))
-3=(y-4)/(x+1)
cross multiplying the equation gives us
y-4=-3(x+1)
y-4=-3x-3
y=-3x-3+4
y=-3x+1
f(x)=-3x+1,voila, you got your linear funciton

since this is is a linear function, you could draw the graph using only the x and y intercepts
which can be found by
i.)letting y=0 for the x intercept
thus,
0=-3x+1
3x=1
x=1/3
therefore your graphed function would cut the x axis at the point (1/3,0)

ii.)letting x=o for the y intercept
thus,
y=-3(0)+1
y=1
therefore your graphed function should cut the y axis at the point (0,1)

HINT: Just plot the points (1/3,0) and (0,1) on the x-y planes and join them using a straight line and you will have graphed your function

Answer 5

if there's anything you haven't quite understood just let me know