Question

how do i solve this question?
4x+4y=16
2x-2y=16
systems of equations are very confusing

Answer 1

it says i have to find the solution by using elimination by addition

Answer 2

Solve for one variable and stick it into the equation.

Let go with and solve for (y):

4x+4y=16
4y=-4x+16
y = -x + 4 now that we know what y equals, plug it into the other equation.

2x -2(-x+4)=16
2x +2x -8= 16
4x = 24
x= 6

We now have a solid value for "x" and can put into the equation that we found for "y"

y = -x +4
y = -(6) +4
y= -2

(6,-2) is the solution to the system of equations.

Answer 3

ok thank you

Answer 4

There are a few ways to find it, but it is best to stick with whatever method you know best and are comfortable with. A test just wants the right answer, not how you get it :)

Answer 5

If you want to solve by addition then:
You have to add a multiple of the second equation to the first equation to try to cancel out the variables. Then carry on with regular algebra to solve for the other variable.

Answer 6

Edit -> cancel out ONE of the variables...