Step-by-step explanation:
The given function is :

(a) To find f(9), put x = 9 in the above expression.

(b) To find f(x+7), put x = x+7 in the above expression.

(c) To find f(-x), put x = -x in the above expression.

Hence, this is the required solution.
Answer:
34 feet
Step-by-step explanation:
From the question, we are told that:
If the room is 30 feet high at the center and 90 feet wide at the floor,
Entire width of the room = 90 feet = 2a
a = 90/2 = 45
Height of the room = b = 30 feet
Foci (c)² = a² - b²
c = √a² - b²
c = √45² - 30²
c = √1125
c = 33.541019662 feet
Approximately to the nearest whole number = 34 feet
Denise and Donna should each stand 34 ft from the outer wall so that they will be positioned at the foci of the ellipse
Answer:-26.25
Step-by-step explanation:
The given expression is

We have to find the discriminant first . And for that, first we need to move whole terms of the left side to right side, that is


The formula of discriminant is

Substituting the values of a,b and c, we will get

And since the discriminant is greater than 0, or it is positive so we have two real roots.
Therefore the correct option is B .