To solve this, plug 3 into x. The equation will be f(3)=-3-2. This simplifies to -5.
Answer: The submarine was 245 feet below sea level after 9 minutes.
Step-by-step explanation: Since y represents minutes, replace it with 9...
-380 + 15(9)
-380 + 135
-245
Since it’s negative, the submarine is still below sea level.
Answer:
5!= 120
Step-by-step explanation:
After 10 weeks, the boys will have same amount in savings.
Step-by-step explanation:
Given,
Roberto already have $30.
Amount saved each week = $5
Let,
x be the number of weeks.
R(x) = 30+5x
Amount saved by Jack each week = $8
J(x) = 8x
For same amount, the functions will be equal.
R(x) = J(x)

Dividing both sides by 3

After 10 weeks, the boys will have same amount in savings.
Keywords: functions, division
Learn more about functions at:
#LearnwithBrainly
<h2>
Answer with explanation:</h2>
Given : In a restaurant, the proportion of people who order coffee with their dinner is p.
Sample size : n= 144
x= 120

The null and the alternative hypotheses if you want to test if p is greater than or equal to 0.85 will be :-
Null hypothesis :
[ it takes equality (=, ≤, ≥) ]
Alternative hypothesis :
[its exactly opposite of null hypothesis]
∵Alternative hypothesis is left tailed, so the test is a left tailed test.
Test statistic : 

Using z-vale table ,
Critical value for 0.05 significance ( left-tailed test)=-1.645
Since the calculated value of test statistic is greater than the critical value , so we failed to reject the null hypothesis.
Conclusion : We have enough evidence to support the claim that p is greater than or equal to 0.85.