Answer:
The least amount of numbers that he can work at his job to have enough for the headphones he wants is 17 hours.
Step-by-step explanation:
To find the number of hours you could divide the cost of the headphones by the amount he earns each hour so you would do $119/ 7 to get 17 and then you could check your answer with multiplication by multiplying 7 * 17 to get 119 which shows that he has to work at least 17 hours to get the headphones he wants.
$119 / 7 = 17
17 * 7 = 119
Solution
For this case we can do the following:
11y - 3x = 18
16y -3x = 33
We can multiply the first equation by -1 and we got:
-11y +3x =-18
16y -3x = 33
_______________
16y -11y = 33-18
5y = 15
y= 15/5 = 3
And then solving for x we got
x = -(18 -11*3)/ 3= -15/3 = 5
Since arc CD is 100 degrees, the rest of the circle must be 260 degrees. Since the rest of the circle is made up of two equal arcs, then arc BC must be half of 260 degrees. Thus, the answer is 130 degrees, C.