SOLUTION: Consider the following system of linear equations 𝑥 + 3𝑦 + 2𝑧 - 𝑤 = −1 −3𝑥 − 7𝑦 + (𝑝 − 6)𝑧 + 2𝑤 = 1 2𝑥 + 𝑝^2𝑧 + 𝑝𝑤 = 𝑞^2 wh

Algebra ->  Equations -> SOLUTION: Consider the following system of linear equations 𝑥 + 3𝑦 + 2𝑧 - 𝑤 = −1 −3𝑥 − 7𝑦 + (𝑝 − 6)𝑧 + 2𝑤 = 1 2𝑥 + 𝑝^2𝑧 + 𝑝𝑤 = 𝑞^2 wh      Log On


   



Question 1205181: Consider the following system of linear equations
𝑥 + 3𝑦 + 2𝑧 - 𝑤 = −1
−3𝑥 − 7𝑦 + (𝑝 − 6)𝑧 + 2𝑤 = 1
2𝑥 + 𝑝^2𝑧 + 𝑝𝑤 = 𝑞^2
where 𝑝 and 𝑞 are real numbers.
Using Gaussian elimination, determine all possible values of 𝑝 and 𝑞 such that the system has no solution.

Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
Write the augmented matrix for the given system of equations.



A augmented matrix has no solution if a row 
has all 0's except for a non-zero element, say 1,
for the rightmost element.  For it would
represent the equation 0x+0y+0z+0w=1.

We try to get a row with all 0's except for
a non-zero element for a rightmost element.
Multiply row 1 by 3 and add to row 2:

matrix%283%2C1%2C3%2C1%2C%22%22%5E%22%22%29



Multiply row 1 by -2 and add to row 3:

matrix%283%2C1%2C-2%2C%22%22%2C1%29



Multiply row 2 by 3 and add to row 3:

matrix%283%2C1%2C%22%22%2C3%2C1%5E%22%22%29



The bottom row will represent an equation with
no solution if:

system%28p%5E2%2B3p-4=0%2C+p-1=0%2Cq%5E2-4%3C%3E0%29

If p=1, the first two equations will be true.
The inequality will hold if q%3C%3E%22%22+%2B-+2

Answer: p=1, q%3C%3E%22%22+%2B-+2

Edwin