Question

How do you graph `y=-1/2` using intercepts?

Answer 1

see explanation.

Explanation:

It helps if we can recognise that lines of the form `color(blue)" y=c and x = c"` where c is a constant, are special cases of the equation of a straight line.

y = c is a straight line, parallel to the x-axis passing through all points in the plane with the same y-coordinate.

`y=-1/2` therefore passes through all points whose y- coordinate is `-1/2` This includes the point on the y-axis, the y-intercept whose coordinates are `(0,-1/2)`

Plotting 3/4 points and drawing a straight line through them gives the graph of `y=-1/2`

For example plot the following set of points.

`(-2,-1/2),(0,-1/2),(2,-1/2)" and " (4,-1/2)`
graph{y-0.001x+1/2=0 [-10, 10, -5, 5]}

I mentioned x = c , which is a line parallel to the y-axis, passing through all points in the plane with the same value of x-coordinate.