is each ordered pair a solution of the given system? write yes or no.

Question

1. y=6x+12
2x-y=4

(-4, -12)

2. Y= -3x
x=4y+1/2

(-1/2,3/2)

3.x+2y=2
2x+5y=2

(6,-2)

4. Solve the system by graphing. Check your solution.
x + y=3
x - y=-1

Answer 1

In order for an ordered pair to be a solution to a system of equations, it must satisfy all equations in the system. So, when you plug the x and the y into each equation, they BOTH must be true to be a solution. If one is true and the other is false, its NOT a solution.

For example, your 3rd question . .
-------------------------------------
Is (6,-2) a solution?
x+2y=2
6+2(-2)=2?
6-4=2?
2=2 (TRUE!)
~~~~~~~~~~~~~~~~~
2x+5y=2
2(6)+5(-2)=2?
12-10=2?
2=2 (TRUE!)

Therefore, the point (6,-2) is a solution

For Graphing, get both equations into y=mx+b. Plot the y-ntercept and then use your slope to find your second point. Draw your graph. Repeat for the other equation. See where the two graphs cross(intersect). That ordered pair is your solution!