Points of inflections are zeroes of the second derivative. We have:

So, the second derivative equals zero if and only if

So, this is the only point of inflection of this function.
Check the picture below
notice, using the 30-60-90 rule, since that triangle is a 30-60-90 triangle, we get 11 = 2x
Mischa wrote the quadratic equation 0 = –x2 + 4x – 7 in standard form
The standard form of quadratic equation is

When y=0 then the standard equation becomes

Now we compare the given equation
with
and find the value of a, b,c
-x^2 can be written as -1x^2
a= -1 , b=4 and c=-7
The value of c is -7
Answer:
15a
Step-by-step explanation:
Because 5(a + a + a) = 5 * (3a) = 15a
We first find value of tax in dollars.
The difference between the two prices is: 23. 54 - 22 = 1.54
Therefore the sales tax in dollars is 1.54
The tax % will be (amount of tax / original cost price ) × 100
(1.54 / 22) × 100 → (0.07) × 100 = 7
So the tax rate is 7%
We can double check the answer.
7 % of 22 → (7/100) × 22 → 0.07 × 22 = 1.54
22 + 1.54 = 23.54