Check the picture below.
notice chord QR is a diameter, thus the vertex at P has a right-angle by Thales theorem.
 
        
             
        
        
        
You need to work about 12.5 hours because from your gas station job, since you work 30 hours every week, times that by 8.75$ which equals 262.5$ at the end of the week, so subtract 262.5 from 400 which is 137.5, then you need to dived that by 11 since its $ per hour, after doing that you get 12.5 hours, so you would have to work 12.5 hours at your landscaper job
        
             
        
        
        
Since you subtract 16 from the y value, P is (-2, 6), and the y value comes second (meaning that it's 6), we get 6-16=-10
        
                    
             
        
        
        
The answer is:  " 9a² + 7a " .
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Note:    (3a)² + 7a = (3a)*(3a) + 7a = 9a² + 7a .
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13°, 66°, and 101° ......