This response is based upon your having had some background in calculus. "dx" is not introduced before that.
Take a look at the sample function y = f(x) = x^2 + 9. Here x is the independent variable; the dependent variable y changes with x.
Now, for a big jump: we consider finding the area under a curve (graph) between x = a and x = b. We subdivide that interval [a,b] into n vertical slices of area. Each of those slices has its own area: f(x)*dx, where dx represents the width of such subarea. f(x)*dx is the actual subarea. To find the total area under the curve f(x) between x= a and x = b, we add up all of these individual subareas between x = a and x = b. Note that the subinterval width is
b-a
dx = ---------- , and that dx becomes smaller and smaller as the number of
n subintervals increases.
Once again, this all makes sense only if you've begun calculus (particularly integral calculus). Do not try to relate it to earlier math courses.
Answer:
The graph of g is the graph of f shifted down 1 unit.
Step-by-step explanation:
Suppose you have a function y = f(x), you can do these following operations on the function:
Shift up a units: y = f(x) + a
Shift down a units: y = f(x) - a
Shift left a units: y = f(x + a)
Shift right a units: y = f(x - a)
In this problem, we have that:
g(x) = -1 + f(x) = f(x) - 1
So the graph of g is the graph of f shifted down 1 unit.
Firstly, you do 90 - 42 to get the amount of brownies sold, which is 48. Then, you put 42 and 48 into a ratio like 42:48. After that, all you need to do is simplify to get 7:8.
