Answer:
15.71
Step-by-step explanation:
 
        
             
        
        
        
(6x+9y=78) - (6x+4y=38) = (5y=40) = y=8
(2x+3(8)=26) = (2x+24=26) = (2x=2) = x=2
 
        
             
        
        
        
Answer: .....
Step-by-step explanation:
 
        
             
        
        
        
Answer:a i belive not 100% sure
Step-by-step explanation:
 
        
             
        
        
        
Answer:
{π/4, 5π/4}
Step-by-step explanation:
Tan theta -1=0 could be rewritten as tan Ф = 1.  The tangent function is 1 at Ф = π/4.  As the period of the tangent function is π,
tan Ф = 1 will be true for Ф = π/4 + π, or (5/4)π.
The solution set is {π/4, 5π/4}.