F(x)=-5t^2+20t+60
Divide everything by -5
f(x)=t^2-4t-12
(t-6)(t+2)
Set it up to zero
t-6=0. t+2=0
t=6. t=-2
Since you can’t have negative seconds, the answer is 6 seconds
Answer:
The equation can define y as a function of x and it also can define x as a function of y.
Step-by-step explanation:
A relation is a function if and only if each value in the domain is mapped into only one value in the range.
So, if we have:
f(x₀) = A
and, for the same input x₀:
f(x₀) = B
Then this is not a function, because it is mapping the element x₀ into two different outputs.
Now we want to see it:
x + y = 27
defines y as a function of x.
if we isolate y, we get:
y = f(x) = 27 - x
Now, this is a linear equation, so for each value of x we will find an unique correspondent value of y, so yes, this is a function.
Now we also want to check if:
x + y = 27
defines x as a function of y.
So now we need to isolate x to get:
x = f(y) = 27 - y
Again, this is a linear equation, there are no values of y such that f(y) has two different values. Then this is a function.
Answer:
Option A is correct.
Step-by-step explanation:
No of Balls in Basketball = 2
No of Balls in Dodge ball = 18
No of Balls in Soccer ball = 8
No of Balls in Tennis ball = 14
Ratio of Soccer balls to Tennis balls = 4 : 7
⇒ For every 4 Soccer ball, there are 7 Tennis ball.
Ratio of Basket ball to Dodge Ball = 1 : 9
⇒ For every 1 Basket ball, there are 9 Dodge balls.
Therefore, Option A is correct.
Answer:
7x - 10
Step-by-step explanation:
f(x)= 5x - 7
g(x)= 2x - 3
f(x) + g(x)
= 5x - 7 + 2x - 3
= 7x - 10
