Answer:
Step-by-step explanation:
a. Since the parabola is compressed by a factor of 1/3 we can state:
- a parabola is written this way : y=(x-h)²+k
- h stands for the translation to the left ⇒ 2*3=6
- k for the units down ⇒4*3=12
So the equation is : y=(x-6)²+12
b.Here the parabola is stretched by a factor of 2 so we must multiply by 1/2
- We khow that a parabola is written this way : y=(x-h)²+k
- (h,k) are the coordinates of the vertex
- the maximum value is 7*0.5=3.5
- we khow tha the derivative of a quadratic function is null in the maximum value
- so let's derivate (x-h)²+k= x²+h²-2xh+k
- f'(x)= 2x-2h h is 1 since the axe of simmetry is x=1
- f'(x)=2x-2 ⇒2x-2=0⇒ x= 1
- Now we khow that 1 is the point where the derivative is null
- f(1)=3.5
- 3.5=(x-1)²+k
- 3.5= (1-1)²+k⇒ k=3.5
So the equation is : y=(x-1)²+3.5
7.
the maximum height is where the derivative equals 0
- h= -5.25(t-4)²+86
- h= -5.25(t²-8t+16)+86
- h=-5.25t²+42t-84+86
- h=-5.25t²+42t+2
Let's derivate it :
- f(x)= -10.5t+42
- -10.5t+42=0
- 42=10.5t
- t= 42/10.5=4
When the height was at max t=4s
- h(max)= -5.25(4-4)²+86 = 86 m
h was 86m
Answer:
give me a minute... if i dont find an answer i will delete my comment
Step-by-step explanation:
Answer:
I'm pretty sure it's c but I'm not sure
Answer:
Number of $5 bills = 32
Number of $10 bills = 14
Number of $20 bills = 8
Step-by-step explanation:
Let x number of $5, y number of $10 and z number of $20
The number of $5 bills exceeds twice the number of $10 bills by 4.
Therefore, x = 2y + 4
The number of $20 bills is 6 fewer than the number of $10 bills.
Therefore, z = y - 6
A wallet contains $460 in $5, $10, and $20 bills.
Therefore,
5x + 10y + 20z = 460
Substitute x and y into equation
5(2y+4) + 10y + 20(y-6) = 460
10y + 20 + 10y + 20y - 120 = 460
40y - 100 = 460
40y = 460 + 100
40y = 560
y = 14
- Put the value of y into x = 2y + 4 and solve for x
x = 2(14) + 4
x = 32
- Put the value of y into z = y - 6 and solve for z
z = 14 - 6
z = 8
Hence, the each type of bills,
Number of $5 bills = 32
Number of $10 bills = 14
Number of $20 bills = 8
