Answer:
There were 3 adults
Step-by-step explanation:
Step 1: Derive the first expression
a+c=10...equation 1
where;
a=number of adults
c=number of children
And total number of people=10
Step 2: Derive the second expression;
Total cost of tickets=(price per child ticket×number of children)+(price per adult ticket×number of adults)
where;
Total cost of tickets=$186.50
price per child ticket=$15.95
price per adult ticket=$24.95
number of children=c
number of adults=a
replacing;
(15.95×c)+(24.95×a)=186.5
24.95 a+15.95 c=186.5....equation 2
Step 3: Combine equation 1 and 2 and solve simultaneously
24.95 a+15.95 c=186.5
-
24.95(a+c=10)
(24.95 a-24.95 a)+(15.95 c-24.95 c)=186.5-(24.95×10)
-9 c=-63
c=-63/-9
c=7
replace the value for c in equation 1
a+c=10
a+7=10
a=10-7
a=3
There were 3 adults
Using a graphing tool
Let's graph each of the cases to determine the solution of the problem
<u>case A)</u>
see the attached figure N 
The range is the interval--------> (0,∞)

therefore
the function
is not the solution
<u>case B)</u> 
see the attached figure N
The range is the interval--------> (0,∞)

therefore
the function
is not the solution
<u>case C)</u>
see the attached figure N
The range is the interval--------> (-∞,3)

therefore
the function
is the solution
<u>case D)</u>
see the attached figure N
The range is the interval--------> (-3,∞)

therefore
the function
is not the solution
<u>the answer is</u>
C. The way the sample was chosen may overrepresent or underrepresent students taking certain language classes.
The samples he chose may not be a representative sample because the number of students per foreign language class may not be the same. Since classes have different numbers of students, one may have a very large number of students while another may have only a few. Taking equal number of students per class is not a representative sample because it doesn't represent the students correctly.
Answer:
1. x=±4
2. t=±9
3. r=±10
4. x=±12
5. s=±5
Step-by-step explanation:
1. x^2 = 16
Taking square root on both sides

x=±4
2. t^2=81
Taking square root on both sides

t=±9
3. r^2-100=0

r=±10
4. x²-144=0
x²=144
Taking square root on both sides

x=±12
5. 2s²=50

s=±5 ..