I am trying to learn Algebra. I'm using Khan Academy, and I just "solved" this problem.
I understand all the steps, except #4.
Could someone please tell me why I would multiply by -1 to simplify the solution?
Mahalo in advance.
Solve for u.
1. Combine constant terms on the right.
2. Factor out the u.
3. Isolate the u.
u=8v−18 / v−5w−4
4. We can simplify this by multiplying the top and bottom by −1.
u= 8v+18 / −v+5w+4