simultaneous equations?

Question

x+y=12


x 0 2 6 12
------------------
y 12 10 6 0

this is an example

how do u work out the equation to find the y numbers?

Answer 1

x+y=12
y=12-x
when x=0 ,y=12-0=12
x=2 ,y=12-2=10
x=6,y=12-6=6
x=12,y=12-12=0
so the ordered pairs are (0,12);(2,10);(6,6);(12,0)
the first value in the parentheses representing the x value and the second value the corresponding value of y

suppose the equation is x-y=8
x=8+y
x=0,y=8-0=8
x=2,y=8-2=6
x=4,y=8-4=4
x=8,y=8-8=0
ordered pairs (0,8);(2,6);(4,4);(8,0)

Answer 2

x+y=12., plug in numbers for X (ie: 6) 6 plus WHAT (y) = 12? Y=6

Simultaneous equations need 2 equations, not just the one.

Answer 3

To solve simultaneous equations, you need the number of equations to equal the number of variables. You have two variables here (x and y) -- but you only have one equation (x+y=12).

I have no idea what that other stuff is at the bottom -- but it isn't an equation.

Answer 4

Don't understand the question For each value of x, you have a corresponding value of y. You need another equation to pin them down to one set. When you have that, solve the original equation for x as a function of y, then subsitute the expression on the right side of that equation for every occurrence of x in the new equation.

x+y=12
x=12-y

So, substitute 12-y for every x in your second equation.

Then solve for y

Answer 5

Solve both equations for y so they read y=... and y=... Equate the two sides of the equation with x and solve for x. Check your work by plugging them into your original equations and solve for Y you should get similar answers.