Question

\[\large {3v_1\over 40} - {v_p\over 40}=0\]
\[\large {v_1\over 40} - {11v_p\over 200} + {v_3 \over 50}=0\]
\[\large {v_p\over 50} - {3v_3\over 25} + {v_4 \over 10}={\frac 1 2}\]
\[\large {v_3\over 10} - {21v_4\over 200} =-3\]

Answer 1

@douglaswinslowcooper
could you check that my equations are correct? also, how do you solve a 4-equations, 4 unknown?

Answer 2

Not sure your equations are correct.
Solving 4 x 4 problem is usually done by solving matrix equation
y =[A]x and if you haven't had this, you won't get it from me!

Sometimes you can find simplifications, as two of your equations have only two unknowns.

Answer 3

haha, I've already taken linear algebra, but I don't recall. Am I supposed to just find the inverse matrix? or do rref?