Answer:
x = -1, y = 2 and z = 1
Step-by-step explanation:
The given system of equations are :
2x - y + 3z= -1 ....(1)
x + 2y - 4z = -1 ......(2)
y – 2z = 0 .....(3)
Equation (3) can be written as :
y = 2z
Use y = 2z in equation (2)
x + 2(2z) - 4z = -1
x + 4z - 4z = -1
x = -1
Put the value of x in equation (1) :
-2 -y +3z = -1
-y+3z = 1 ....(4)
Adding equation (3) and (4)
y-2z+(-y+3z)=1
z = 1
Now put z = 1 in equation (4)
-y+3=1
-y = -2
y = 2
Hence, the values of x,y and z are -1, 2 and 1 respectively.
The <em>instantaneous</em> rate of change of <em>g</em> with respect to <em>x</em> at <em>x = π/3</em> is <em>1/2</em>.
<h3>How to determine the instantaneous rate of change of a given function</h3>
The <em>instantaneous</em> rate of change at a given value of
can be found by concept of derivative, which is described below:

Where
is the <em>difference</em> rate.
In this question we must find an expression for the <em>instantaneous</em> rate of change of
if
and evaluate the resulting expression for
. Then, we have the following procedure below:




Now we evaluate
for
:

The <em>instantaneous</em> rate of change of <em>g</em> with respect to <em>x</em> at <em>x = π/3</em> is <em>1/2</em>. 
To learn more on rates of change, we kindly invite to check this verified question: brainly.com/question/11606037
Meter is 0.5 and the fraction is I think 1/2
Plug x=3 into the equation:
5(3)+2
And simplify:
15+2
17