Answer:
y
=
−
√
4
x
+
19
Step-by-step explanation:
The total number of problems she needs to grade is 6.
A) zeroes
P(n) = -250 n^2 + 2500n - 5250
Extract common factor:
P(n)= -250 (n^2 - 10n + 21)
Factor (find two numbers that sum -10 and its product is 21)
P(n) = -250(n - 3)(n - 7)
Zeroes ==> n - 3 = 0 or n -7 = 0
Then n = 3 and n = 7 are the zeros.
They rerpesent that if the promoter sells tickets at 3 or 7 dollars the profit is zero.
B) Maximum profit
Completion of squares
n^2 - 10n + 21 = n^2 - 10n + 25 - 4 = (n^2 - 10n+ 25) - 4 = (n - 5)^2 - 4
P(n) = - 250[(n-5)^2 -4] = -250(n-5)^2 + 1000
Maximum ==> - 250 (n - 5)^2 = 0 ==> n = 5 and P(5) = 1000
Maximum profit =1000 at n = 5
C) Axis of symmetry
Vertex = (h,k) when the equation is in the form A(n-h)^2 + k
Comparing A(n-h)^2 + k with - 250(n - 5)^2 + 1000
Vertex = (5, 1000) and the symmetry axis is n = 5.
<em>Answer:</em>
<em>n = 12</em>
<em>Step-by-step explanation:</em>
<em>85%×n = 10.2</em>
<em>85n/100 = 10.2</em>
<em>85n = 1020</em>
<em>n = 1020 : 85</em>
<em>n = 12</em>
Answer:
y=-3x+2
Step-by-step explanation:
as x goes up on y goes down 3
slope is change in y over change in x
-3/1=-3
the y intercept is (0,2) so the y intercept is +2
