SOLUTION: Hi! I tried to solve this system by using the graph method but, when I check it with my colleagues, the result is not correct and I do not understand why. The system is: 3x-y=7 , -

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: Hi! I tried to solve this system by using the graph method but, when I check it with my colleagues, the result is not correct and I do not understand why. The system is: 3x-y=7 , -      Log On


   

Question 1199230: Hi! I tried to solve this system by using the graph method but, when I check it with my colleagues, the result is not correct and I do not understand why. The system is: 3x-y=7 , -12x+4y=3. The values that I decided to use for x were: 0,1,2. Thank you in advance for any help you can give me.
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Your given system: system%283x-y=7%2C-12x%2B4y=3%29

---removed----

NO! ... Slopes of both given lines are -3. the two lines are parallel.


-y=-3x%2B7
y=3x-7
slope is 3;
-
4y=12x%2B3
y=3x%2B3%2F4
slope also 3;

Both lines parallel - no points in common

Answer by ikleyn(52787) About Me  (Show Source):
You can put this solution on YOUR website!
.

Correction to the incorrect solution by @josgarithmetic. 

    Both lines have the same slope, equal to 3.

    It means that the lines are parallel (and they do not coincide).

    Hence, the given system of equations has no solution/solutions.

Solved and explained.