Answer:
u = 2
Step-by-step explanation:
7u - 5u = 4
When you have two terms with the same variable, you can subtract their coefficients.
7u - 5u = 4
This is because 7u = u + u + u + u + u + u + u and 5u = u + u + u + u + u.
So if you did this:
(u + u + u + u + u + u + u) - (u + u + u + u + u) = u + u
You would still get the same answer; the other one is just a less repetitive way to express it.
7u - 5u = 4
2u = 4
Now you divide both sides by 2.
(2u)/2 = 4/2
u = 2
And end up with u = 2!
