Answer:
B
Step-by-step explanation:
The vertex is the turning point of the parabola.
First find the zeros by equating y to zero, that is
(x - 6)(x + 12) = 0
Equate each factor to zero and solve for x
x - 6 = 0 ⇒ x = 6
x + 12 = 0 ⇒ x = - 12
The vertex lies on the axis of symmetry which is situated at the midpoint of the zeros, thus
=
=
= - 3
Thus the x- coordinate of the vertex is x = - 3 → B
Answer:
Step-by-step explanation:
Let x and y are the two positive real numbers
product of two numbers is 21
The sum of the two numbers is f(x) =x+y
Replace y with 21/x
we need to find smallest possible sum , so we take derivative using power rule
when sum is minimum then the derivative is equal to 0
multiply both sides by x^2
Take square root on both sides
