Answer:
(-1, 10/3)
x = -1
y = 10/3
Step-by-step explanation:
To solve a system, one of the methods you can use is <u>elimination</u>. To use elimination, you need <u>a variable to have the same coefficient in BOTH equations</u>. Since both equations have "3y", with the same coefficient (3), we can use this method.
We want to eliminate a variable by cancelling it out. Since positive 3y PLUS negative 3y is 0, the variable in eliminated. ADD each of the terms in the equations together.
. x + 3y = 9
<u>+ 3x – 3y = -13</u>
. 4x – 0y = -4 3y - 3y = 0
. 4x = -4 Divide both sides by 4 to isolate 'x'
. x = -1 Solved for the x-coordinate
Since we know one variable, 'x', we can easily find the other, 'y'. Substitute 'x' with -1 in any of the equations. Then, isolate 'x'.
x + 3y = 9
(-1) + 3y = 9
-1 + 1 + 3y = 9 + 1 Add 1 to both sides to cancel out left side.
3y = 9 + 1 Add on the right side (9 + 1 = 10)
3y = 10 Divide both sides by 3 to isolate 'y'
y = 10/3 Solved for the y-coordinate
Put the 'x' and 'y' coordinates together in an ordered pair, which you write as (x, y).
The solution to the system is (-1, 10/3).
