Question

Use the graph method to solve the system of linear equations:

2x + y = 3 and x + y = 3


A) (-1.5, 0)
B) (0, -1.5)
C) (0, 3)
D) (3, 0)

Answer 1

C) (0, 3)

Explanation:

You want to look at where the lines intercept. Also, 0+3 is 3, from the first equation the problem gives you, it says 2x+y=3 substitute you coordinates into the equation and your overall numbers equal 3.

Answer 2

`\left\{\begin{array}{ccc}2x+y=3&|-2x\\x+y=3&|-x\end{array}\right\\ \left\{\begin{array}{ccc}y=-2x+3\\y=-x+3\end{array}\right\\\\y=-2x+3\\for\ x=0\to y=-2(0)+3=3\to(0;\ 3)\\for\ x=3\to y=-2(3)+3=-6+3=-3\to(3;-3)\\\\y=-x+3\\for\ x=0\to y=-0+3=3\to(0;\ 3)\\for\ x=3\to y=-3+3=0\to(3;\ 0)\\\\Answer:\ C)\ (0;\ 3)`