Answer:
none of the above
Step-by-step explanation:
The grocer's revenue will be the product of the number of loaves sold (30-2x) and their price (2.50+0.50x).
Revenue will be positive for values of x between those that make these factors be zero. The number of loaves sold will be zero when ...
... 30 -2x = 0
... 15 -x = 0 . . . . . divide by 2
... x = 15 . . . . . . . add x
The price of each loaf will be zero when ...
... 2.50 +0.50x = 0
... 5 + x = 0 . . . . . . . multiply by 2
... x = -5 . . . . . . . . . . subtract 5
Revenue will be positive for any number of increases greater than -5 and less than 15.
_____
D is the best of the offered choices, but it is incorrect in detail. -5 is a number less than 15, but will give zero revenue.
Answer:
B) A random sample may represent the population <em>is your best answer.</em>
Step-by-step explanation:
Note that the answer choice says "may", which means that it doesn't <em>always</em> represent the population. Random samples means that they ask random people, and do not have a certain rule that they have to follow (such as recipients can only be a certain race, age, etc.) and that they can ask anybody they meet. This can give not only a higher chance of a general population's opinion, but also makes sure that there is not a high chance of obtaining misleading information.
For example, a random survey would not take place at a rally, in which most of the people would believe the same thing, and would answer fairly the same for the survey. Instead, a random survey may be taken at a busy intersection during the time when most people are out. You must note that though it has the best chance of getting a <em>more accurate</em> representation, it still isn't the most accurate. For the best accuracy, <em>everyone would have to answer the survey in which the survey question would affect</em>.
~
Answer:
negative because the container is losing liquid.
Step-by-step explanation:
y-5x is the rate
15 divide 30 by 2 and you have your answer
Problem:
Solve
2
x
+
5
y
=
−
3
;
3
x
−
y
=
21
Steps:
I will try to solve your system of equations.
3
x
−
y
=
21
;
2
x
+
5
y
=
−
3
Step: Solve
3
x
−
y
=
21
for y:
3
x
−
y
+
−
3
x
=
21
+
−
3
x
(Add -3x to both sides)
−
y
=
−
3
x
+
21
−
y
−
1
=
−
3
x
+
21
−
1
(Divide both sides by -1)
y
=
3
x
−
21
Step: Substitute
3
x
−
21
for
y
in
2
x
+
5
y
=
−
3
:
2
x
+
5
y
=
−
3
2
x
+
5
(
3
x
−
21
)
=
−
3
17
x
−
105
=
−
3
(Simplify both sides of the equation)
17
x
−
105
+
105
=
−
3
+
105
(Add 105 to both sides)
17
x
=
102
17
x
17
=
102
17
(Divide both sides by 17)
x
=
6
Step: Substitute
6
for
x
in
y
=
3
x
−
21
:
y
=
3
x
−
21
y
=
(
3
)
(
6
)
−
21
y
=
−
3
(Simplify both sides of the equation)
Answer:
y
=
−
3
and
x
=
6
