Answer:
Step-by-step explanation:
Let c be cost of each call and t represent cost of each text message.
We have been given that last week Ricki made 4 call and sent 20 text messages which cost him $4.
Cost of 4 calls would be .
Cost of 20 text messages would be
Total cost id $4.00.
We can represent this information in an equation as:
We are also told that this week he made 10 calls and sent 5 text messages which cost him $5.50.
Cost of 10 calls would be .
Cost of 5 text messages would be
Total cost id $5.50.
We can represent this information in an equation as:
Therefore, our required system would be:
Let's begin with <span>f(x) = a(x-h)^2+ k. Note that we must use "^" to indicate exponentiation. Write (x-h)^2, not (x-h)2.
If (-3,4) is the vertex, then the above equation becomes f(x) = a(x-[-3])^2 + 4, or
f(x) = a(x+3)^2 + 4. We are told that the graph passes through (-1,0), so must now substitute those coordinates into the above equation:
f(-1) = a([-1]+3)^2 + 4 = 0 (0 is the value of f when x is -1)
Then we have a(2)^2 + 4 =0, or 4a + 4 = 0. Thus, a = -1.
The equation of this parabola is now f(x) = -(x+3)^2 + 4.
Write it in "standard form:" f(x) = -(x^2 + 6x + 9) + 4, or
f(x) = -x^2 - 6x - 9 + 4, or
answer => f(x) = -x^2 - 6x - 5 = ax^2 + bx + c
Thus, a=-1, b=-6 and c= -5.</span>
V=1/3*πr² *h,
raduus r=32/2=16
V=1/3*3.14*(16)² *18=6*3.14*(16)² =4823.04