(1) 3x+6y-12z=36
(2) x+2y-4z=12
(3) 4x+8y-16z=48
The first equation (1) is the second equation (2) multiplied by 3:
(2) x+2y-4z=12→3(x+2y-4z=12)→3x+6y-12z=36 (1)
The third equation (3) is the second equation (2) multiplied by 4:
(2) x+2y-4z=12→4(x+2y-4z=12)→4x+8y-16z=48 (3)
The equations are linearly dependent, Then the system of equations is dependent, and then consistent too.
Answer:
A
Step-by-step explanation:
The theorem we use for this is

Solve for d.



A is the answer
Answer: Hello mate!
Clairaut’s Theorem says that if you have a function f(x,y) that have defined and continuous second partial derivates in (ai, bj) ∈ A
for all the elements in A, the, for all the elements on A you get:

This says that is the same taking first a partial derivate with respect to x and then a partial derivate with respect to y, that taking first the partial derivate with respect to y and after that the one with respect to x.
Now our function is u(x,y) = tan (2x + 3y), and want to verify the theorem for this, so lets see the partial derivates of u. For the derivates you could use tables, for example, using that:


and now lets derivate this with respect to y.
using that 

Now if we first derivate by y, we get:

and now we derivate by x:

the mixed partial derivates are equal :)
Answer:
3/4
Step-by-step explanation:
4x+6 = 8x+3
Subtract 4x from both sides to get x on the same side
6 = 4x+3
Subtract 3 from both sides:
3 = 4x
Divide by 4:
x = 3/4