Answer:
Second option
Third option
Fourth option
Step-by-step explanation:
We have the following quadratic function
Use the distributive property to multiply the expression
For a function of the form 
the x coordinate of the vertex is:
Then in this case the coordinate of the vertex is:
To obtain the y coordinate of the vertex we evaluate the function at 
Then the vertex is: (-3, -16)
We can see in the graph that the zeros of the function are x=1 and x=-7
Then the function is decreasing from -∞ to -3 and then it is increasing from -3 to ∞
The function is positive for 
and 
The correct answers are:
Second option
Third option
Fourth option
Answer:
25 seconds
Step-by-step explanation:
Skydiving.
height (in feet) above the earth=h(t)= -16t^2 + 10,000
the time it would take to fall when h is 0
-16t^2 + 10,000=0
-16t^2=-10000
16t^2=10000
t^2=10000/16=625
t=sqrt 625=25 seconds
Yes I worked it in my brain hahahahahah
Let the actual value of the stool be x.
So if the carpenter sells the stool x rupees he neither loses, now wins anything.
67.50 is the value x - 10% of x, that is:
67.50=x-0.1x
67.50=0.9x
x=67.50/0.9=75 (rupees) is the actual value of the stool.
Selling the stool for 82.50 rupees, the carpenter clearly would make a profit, say of y% of that actual value, that is y%*75.
So using the same method:
82.50=75+y%*75
y%*75=82.50-75=7.5
we can make the calculations, but clearly 7.5 is 10% of 75
Answer: 10% gain.
