Question

How do you graph the linear function `f(x)=-x+4`?

Answer 1

See a solution process below:

Explanation:

First, solve for two points which solve the function and plot these points:

First Point: For `x = 0`

`f(0) = -0 + 4`

`f(0) = 4` or `(0, 4)`

Second Point: For `x = 4`

`f(4) = -4 + 4`

`f(4) = 0` or `(4, 0)`

We can next plot the two points on the coordinate plane:

graph{(x^2+(y-4)^2-0.075)((x-4)^2+y^2-0.075)=0 [-20, 20, -10, 10]}

Now, we can draw a straight line through the two points to graph the line:

graph{(y+x-4)(x^2+(y-4)^2-0.075)((x-4)^2+y^2-0.075)=0 [-20, 20, -10, 10]}

Answer 2

`"see explanation"`

Explanation:

`"one way is to find the intercepts, that is where the graph"`
`"crosses the x and y axes"`

`• " let x = 0, in the equation for y-intercept"`

`• " let y = 0, in the equation for x-intercept"`

`x=0rArry=4larrcolor(red)"y-intercept"`

`y=0rArr-x+4=0rArrx=4larrcolor(red)"x-intercept"`

`"Plot the points "(0,4)" and "(4,0)`

`"Draw a straight line through them for graph"`
graph{(y+x-4)((x-0)^2+(y-4)^2-0.04)((x-4)^2+(y-0)^2-0.04)=0 [-10, 10, -5, 5]}