The ordered pair that is the best estimate for the solution of the system of equations is (7, 1/2)
The given system of equations is:

Equate equations (1) and (2)

Solve for x in the equation above

Substitute x = 7 into equation (1)

The ordered pair that is the best estimate for the solution of the system of equations is (7, 1/2)
Learn more on system of equations here: brainly.com/question/13729904
X^3 - 21x = -20add 20 to both sidesx^3 - 21 x + 20 = 0Rational Root Theorem:Factors of P (constant) 20 = 1, 2, 4, 5, 10, 20------------------------------- Factors of Q (leading Coefficient) = 1
Possible zeros (all + -) 1/1, 2/1, 4/1, 5/1, 10/1, 20/1
Of the choices given only the number 1 is a possible root.
At $7.50 per soccer ball, they earn a daily profit of $232.50.
The store needs to earn a daily profit of $400 – $232.50 = $167.50 from footballs.
Solve 167.50 = –4x2 + 80x – 150 to find the price for footballs: x = $5.46 and $14.54.
A true equation from these numbers can be:
82 ÷ 2 = 41 ÷ 2 = 20.5
Hope this helps!
Answer: ± 1.96
Step-by-step explanation:
Given the following :
Mean (m) time spent = 11.85
Standard deviation = 4 minutes
Since the population of site visits is Normally distributed, Hence, the test statistic will follow a normal distribution :
The test the hypothesis that mean time has changed at 0.05 confidence interval
Normal distributions have a mean value of 0 and standard deviation of 1
Using a two tailed test At 0.05 confidence interval ;
Using the critical value calculator, which in general under normal distributions :
0.05% confidence interval for a two tailed test is
± 1.96