Question

How do you graph `y=x+4` by plotting points?

Answer 1

See a solution process below:

Explanation:

For a linear function you only need to plot two points. First, solve for two points which solve the equation and plot these points:

First Point: For `x = 0`

`y = 0 + 4`

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

Second Point: For `x = 2`

`y = 2 + 4`

`y = 6` or `(2, 6)`

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

graph{(x^2+(y-4)^2-0.1)((x-2)^2+(y-6)^2-0.1)=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)^2-0.1)((x-2)^2+(y-6)^2-0.1)=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=0toy=0+4rArry=4larrcolor(red)"y-intercept"`

`y=0to0=x+4rArrx=-4larrcolor(red)"x-intercept"`

`"plot the points "(0,4)" and "(-4,0)`

`"and draw a straight line through them"`
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]}