B)
By elimination:
Adding the equations we'll eliminate and we get
Now, plug y in the first (or second) equation and find x.
By substitution:
From the first equation .
Substitute y in the second equation and solve for x.
Graphically:
Hey guys it has been so long since I have done a lot of algebra and I am working on this take home assignment and am trying hard to figure out how to tackle some of these.
The instructions state: "Solve the following systems of equations by elimination, substitution, or graphically.
A 3x-y=6 & x+4y=3 B y+2=-x^2+1 & x2+1=2y+6 C x-2y+3z=10 & 2x-3y-z=8 & 5x-9y+8z=20
For A I got X being 2 1/3 and Y being 3. I am struggling on the other two. Any help is appreciated.
C)
By elimination:
We'll eliminate z:
Multiply the second equation by 3 and add to the first:
(1)
Multiply the second by 8 and add to rhe third:
(2)
Now, multiply (1) by -3 and add to (2):
, which is obviously false. So the system has no solution.
By substitution:
From the first equation
Substitute x in the others two equations and you'll obtain a system in y and z. Apply the same method to this system.