Answer:
20% decrease.
Step-by-step explanation:
difference over original
50.97-40.78= 10.19
diff/orig=sales tax
10.19 / 50.97= 19.99..
19.99 is approximately 20.
Answer:
f(x)= (x-3)^2-3
Step-by-step explanation:
Vertex Form: y= a(x-h)^2+k
a is the reflection
h and k are the vertex so in an ordered pair (x,y) = (h,k)
Since it is translating 3 units down it is going to be a negative 3. If it was translating up it would be positive 3. This represents the "k" because it is moving on the y-axis.
Since it is translating 3 units to the right it is going to be positive 3. If it was translating left it would be negative 3. This represents the "h" because it is moving on the x-axis.
After plugging it into the vertex form formula: f(x)= (x-3)^2-3
*notice when I plugged the "h" in it became negative because x-(3)= x-3*
Hmm, the 2nd derivitve is good for finding concavity
let's find the max and min points
that is where the first derivitive is equal to 0
remember the difference quotient
so
f'(x)=(x^2-2x)/(x^2-2x+1)
find where it equals 0
set numerator equal to 0
0=x^2-2x
0=x(x-2)
0=x
0=x-2
2=x
so at 0 and 2 are the min and max
find if the signs go from negative to positive (min) or from positive to negative (max) at those points
f'(-1)>0
f'(1.5)<0
f'(3)>0
so at x=0, the sign go from positive to negative (local maximum)
at x=2, the sign go from negative to positive (local minimum)
we can take the 2nd derivitive to see the inflection points
f''(x)=2/((x-1)^3)
where does it equal 0?
it doesn't
so no inflection point
but, we can test it at x=0 and x=2
at x=0, we get f''(0)<0 so it is concave down. that means that x=0 being a max makes sense
at x=2, we get f''(2)>0 so it is concave up. that means that x=2 being a max make sense
local max is at x=0 (the point (0,0))
local min is at x=2 (the point (2,4))
Answer:
Change = -(1/2) * 30 = -15 inches
Step-by-step explanation:
If the water level decreases by 1/2 inch each day, the change in the water level in one day is -1/2 inch.
So, after t days, the total change in the water level can be calculated as:
Total change = -(1/2) * t inches
So, after 30 summer days, the total change is:
Change = -(1/2) * 30 = -15 inches
So the water level of the pool after 30 summer days has decreased by 15 inches.
