Answer:
x<7
Step-by-step explanation:
-8x+40>-16
No, (2 , 3) does not satisfy the inequality 4x + 3y > 20.
See attached picture:
~
<h2>
Answer with explanation:</h2>
Let
be the population mean.
By observing the given information, we have :-

Since the alternative hypotheses is left tailed so the test is a right-tailed test.
We assume that the time spend by students per day is normally distributed.
Given : Sample size : n=121 , since n>30 so we use z-test.
Sample mean : 
Standard deviation : 
Test statistic for population mean :-


Critical value (one-tailed) corresponds to the given significance level :-

Since the observed value of z (-7.79) is less than the critical value (1.2816) , so we do not reject the null hypothesis.
Hence, we conclude that we have enough evidence to accept that the college students spend an average of 4 hours or less studying per day.
Step-by-step explanation:
8x + x² - 2y + y² - 64 = 0
(x + 4)² + (y - 1)² - 81 = 0
(x + 4)² + (y - 1)² = 81
Hencr the center is (-4,1) and the radius is 9.