Answer:
x = 13 y = - 10 z = -5
Step-by-step explanation:
In the augmented matrix of a system of linear equation, each row represent an equation, and each column represent variables and constants
Therefore the linear equation for the augmented matrix
1 2 -2 : 3
0 1 1 : -15
0 0 1 : -5
Is in terms of x y z and w, the equation system:
1*x + 2*y - 2*z = 3
0*x + 1* y + 1*z = -15
0*x + 0*y + 1*z = -5
To solve it we proceed as follows
from the last equation z = - 5
plugging this value in the second equation
y + z = - 15
y - 5 = - 15
y = - 10
And finally
x + (2)*(-10) - 2*( - 5 ) = 3
x - 20 + 10 = 3
x - 10 = 3
x = 13
