Answer:
45
Step-by-step explanation:
Answer:
D infitently Many
Step-by-step explanation:
A system of linear equations usually has a single solution, but sometimes it can have no solution (parallel lines) or infinite solutions (same line). This article reviews all three cases. One solution. A system of linear equations has one solution when the graphs intersect at a point.
It's dependent on the context. A book may ask you to find the f'(x) of a function and you may have to use a u sub in your problem which requires you to find the dy/dx of what you substitute. So in this case both would be used.
I = PRT
21 = 200 * 0.035 * T
21 = 7T
3 years = T
