For this case we must solve the following quadratic equation:

Where:

The solution is given by:

Substituting:

Thus, we have two roots:

ANswer:

 
        
             
        
        
        
-  <em>0</em><em>.</em><em>0</em><em>0</em><em>5</em><em> </em><em><u>></u></em><em><u> </u></em><em> </em><em>0</em><em>.</em><em>0</em><em>5</em>
<h2><em>hope </em><em>it</em><em> helps</em><em>!</em></h2>
 
 
        
                    
             
        
        
        
The <em><u>correct answers</u></em> are:
B- x + y ≤ 10
; and D- x ≥ 4
Explanation:
The illusionist needs at least 4 female volunteers.  This means he could use 4 or more; this means x, the number of female volunteers, is greater than or equal to 4:
x ≥ 4
The total of number of volunteers needed is up to 10.  This means the illusionist can use 10 or fewer people; this means the total is less than or equal to 10.
The number of female volunteers is x and the number of male volunteers is y; together they create the expression x+y.  This gives us
x+y ≤ 10