Answer:
Chris will take 0.75 seconds to return to his starting height of 10 feet.
Step-by-step explanation:
Let the height of Chris be represented by 
, where 
is the height in feet and 
, the time in seconds. First, we equalize the formula to a height of 10 feet and simplify the resulting expression, that is:
Then, we simplify the expression by algebraic means:
Roots of the polynomial are, respectively:
First root represents the initial height of Chris, whereas the second one represents the instant when Christ returns to the same height above the surface of the water. Hence, Chris will take 0.75 seconds to return to his starting height of 10 feet.
Answer:
D
Step-by-step explanation:
It just is
Answer:
a) 38"
b) L = 5.7'
Step-by-step explanation:
a) Given
P = 9,500 lb/ft
Thick = 18"
We assume an allowable bearing pressure of σ = 3000 lb/sf
If Stress = Force / Area
σ = P/A
Solving for area
A = P/σ ⇒ A = 9,500 lb/ft/3000 lb/sf
⇒ A = 3.167 sf, or 3.167 ft wide, per foot of length.
⇒ A = 38" wide
We can see the pic 1 in order to understand the answer.
b) Given
P = 65,000 pounds = 65,000 lb
Thick = 18" = 1.5'
We assume an allowable bearing pressure of σ = 2000 lb/sf
If Stress = Force / Area
σ = P/A
Solving for area
A = P/σ ⇒ A = 65,000 lb/2000 lb/sf
⇒ A = 32.5 sf
then A = L² ⇒ L = √A = √(32.5 sf) = 5.7 ft
Finally L = 5.7'
We can see the pic 2 in order to understand the answer.
Answer:
f(x)= -(x^3+10x^2-275x-1500) Standard
f(x)= -(x+20)(x+5)(x-15)
Step-by-step explanation:
The factored form of the equation is:
(x+20)(x+5)(x-15)=f(x) Each of the zeroes are where the graph crosses the x-axis.
The expanded form of the equation is found by using FOIL on the equations above:
-x^3+10x^2-275X-1500
The leading coefficient is negative because the graph rises to the left and falls to the right.
|-6| + |-3 + (-5)|
6 + |-8|
6 + 8
14
