Posted by **Sam** on Sunday, June 13, 2010 at 8:05am.

How do I find the set of all points of y=-8 on a graph?

- Math/209 -
**Reiny**, Sunday, June 13, 2010 at 9:48am
Any equation in x and y merely gives you a description of the relationship between the x and y coordinates of the points in a relation.

e.g.

x=y = 6 means that as long as the x and the y of a given point add up to 6, that point belongs.

So in your case it says that y = -8 , with no mention of x.

That means that we don't put any restriction on x and x can be anything we want it to be

as long as our y is -8, anything goes

so some points:,

(1,-8), (5,-8), (-3,-8), (3.56,-8), (√2,-8), (0,-8), ...

- typo - Math/209 -
**Reiny**, Sunday, June 13, 2010 at 9:50am
4th line should have been

x+y = 6 means that as long as the x and the y of a given point add up to 6, that point belongs.

but you probably guessed that anyway.

- Math/209 -
**Sam**, Sunday, June 13, 2010 at 11:05am
Can you please explain to me how you find teh points, such as (1,-8) and (-3,-8)are mulitilying, adding, what exactly do I have to do to get this?

- Math/209 -
**Reiny**, Sunday, June 13, 2010 at 12:26pm
As I stated, since there is no x in your equation, x can be any value you want it to be, as long as the y value is -8.

so I just made up any x I could think of.

There is no mathematical operation involved at all, since all it said that y = -8 or

"the y value has to be -8"

## Answer this Question

## Related Questions

Math - The graph of the equation y=4-x consists of all the points in the ...

Calculus - assume that f(x)= x^3(x-2)^2 a) find the x-intercepts algebraically b...

implicit diffirentation - y4 + xy = x3 – x + 84 (a) Find dy/dx at the two points...

calculous - 3.Given the function f defined by f(x)=2x^3-3x^2-12x+20 a.Find the ...

math - Question-2; Consider the function f(x)= -cos3x -4sin3x. (a)Find the ...

precalculus - analyzethe graph of the function Find the x- and y-intercepts. (b...

Calc - 1. Find values of a,b,c, and d such that g(x) = a(x^3)+b(x^2)+cx+d has a ...

calculus (derivativs) - Find the points on the graph of f where the tangent line...

Calculus - Graph the function f(x)=x+4/x Graph the secant line that passes ...

Geometry Check - Which set of points are collinear? a.)A(-1,5); B(2,6); C(4,7) b...