solve this system: 3x+2y=-6, x+3y=-2graph them in one graph
2 Answers
hala718 | High School Teacher | (Level 1) Educator Emeritus
3x+ 2y = -6 ...........(1)
x + 3y = -2 ..............(2)
First we will solve algebraically.
Multiply (2) by -3 and add to (1).
==> 3x + 2y = -6
==> -3x -9y = 6
==> -7y = o ==> y= 0
==> 3x = -6 ==> x = -2
Then, the solution is the point (-2,0)
Now we will verify by graphing both lines.
3x+2y = -6 ( black line)
x+ 3y = -2 (red line)
You can see that both lines intersects at the point (-2, 0) which is the solution of the system.
atyourservice | Student, Grade 11 | (Level 3) Valedictorian
3x+2y=-6, x+3y=-2
I'll start out with the second equation since it is easier for me that way:
x+3y=-2
subtract 3y from both sides:
x = -2 - 3y
now we know what x is (for now) plug it in as x into any of the problems above:
3(-2 - 3y) + 2y = -6
simplify:
-6 - 9y + 2y = -6
combine like terms:
-6 - 7y = -6
add 6 to both sides:
-7y = 0
divide
y = 0
plug in this result into any of the problems:
x+3(0) =-2
x = -2
( -2, 0)