A closed dot mean "greater than or equal to" or "less than or equal to"
An open dot means "less than" or "greater than"
In this case, an open dot would mean
X>-2
The first one is 1.12867 because you need to set it up like this.
4=3.14(x)squared
4/3.14=x(squared)
x=1.12867
The second one is done simply by multiplying it out.
A=3.14(3x)squared
A=3.14(9x[squared])
A=28.26x[squared] -The squared is referring to the x.
9514 1404 393
Answer:
x = (ab +a +b +c)/(a +b)
Step-by-step explanation:
Eliminate parentheses, subtract left terms not containing x, divide by the coefficient of x.

to average 60 mph for 2 laps his total speed needs to equal 60 x 2 = 120
his first lap was 40 so his 2nd lap needs to be 120-40 = 80 mph
B, because you can't get the square root of a negative number