Answer:

Step-by-step explanation:
Let x represents the number of nights Jack worked and y represents the number of nights Diane worked.
1. The number of nights Diane is scheduled to work is no more than four times the number of nights Jack is scheduled to play. Then

2. Diane will work at least 10 times before the concert. Then

3. Jack earns $50 per night that he plays, then he earned $50x in x nights. Diane earns $25 each night she works, then she earns $25y in y nigths. They need at least $750, so

4. We get the following set of constraints to model the problem:

The absolute value of x is 4
Answer:
0, -1
Step-by-step explanation:
zeros occur when 2x^6+2x^5=0
the first way for this to happen would be to set x to 0. both terms would become zero.
the second way is x = -1
first term becomes 2
second becomes -2
these add to zero
Complete question is: Each bicycle have speed 10 mi/h and fly flies at 21 mi/h. How far the fly flies?
Answer:
47.25 mi
Step-by-step explanation:
The relative velocity of the bicycles is 10+10 = 20 mi/h
Time in which the two bicycles meet:

Distance covered by fly:

Set up an equation to solve.
$8.50x (since it is the rate of change) + $12 (flat fee) = total money earned (or y). In this case, we have the total, amount, and are looking for x. Plug $139.50 into the equation.
$8.50x + $12 = $139.50
Now, solve for x.
$8.50x + $12-12 = $139.50-12 > <em>$8.50x = $127.5</em>
$8.50/8.50x = $127.5/8.50 > <em>x = 15</em>
So, the correct answer is <u>D. Olivia babysat for 15 hours.</u>