Answer:
Happy new year to you and your family and
we know that
A relationship between two variables, x, and y, represent a proportional variation if it can be expressed in the form y=kx
where
k is the constant of proportionality
Verify each table
table a
Let
x ----> distance
y ----> sound level
For each ordered pair calculate the value of k
k=y/x
so
(5,85) -----> k=85/5=17
(10,79) ----> k=79/10=7.9
the values of k are differents
that means
the table nor represent a proportional relationship
table b
let
x ----> volume
y ----> cost
k=y/x
(16,1.49) ----> k=1.49/16=0.093125
(20,1.59) ----> k=1.59/20=0.0795
the values of k are differents
that means
the table nor represent a proportional relationship
Answer:
Step-by-step explanation:
9x⁴ – 2x² – 7 = 0
Let's say that u = x²:
9u² – 2u – 7 = 0
Factor:
(u – 1) (9u + 7) = 0
u = 1, -7/9
Since u = x²:
x² = 1, -7/9
x = ±1, ±i √(7/9)
I think its B but ima have to check again and get back to you
Equation B is written in vertex form, which means you can read the vertex (extreme value) from the numbers in the equation.
Vertex form is
y = a(x -h)² + k
where the vertex (extreme point) is (h, k). Whether that is a maximum or a minimum depends on the sign of "a". When "a" is negative, the graph is a parabola that opens downward, so the vertex is a maximum.
Equation
B reveals its extreme value without needing to be altered.
The extreme value of this equation is a
maximum at the point
(2, 5).