Answer:
Answer C is correct
Step-by-step explanation:
-200(3/4) = -600/4 = -150 ft
Answer:
Let width = w
length = 4w/3
Area = 432 = length*width = w*4w/3
4w^2/3 = 432
w^2 = 432*3/4 = 324
w = 18
so the width of the cake pan is 18 inches.
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.
Let
R = Ralph's age
S = Sara's age
First statement is translated as:
S = 3R
Second statement is translated as:
S + 4 = 2(R + 4)
Use the first equation to be substituted into the second one in terms of R which is the one we are actually going to solve for Ralph's age.
Since S = 3R, then
3R + 4 = 2(R + 4)
3R + 4 = 2R + 8
3R - 2R = 8 - 4
R = 4 years old