In a triangle, the total angle is 180 degrees. A straight line is always 180 degrees. With this in mind, the following can be obtained:

These are simultaneous equations. 

 
        
                    
             
        
        
        
Answer:
$7.65
Step-by-step explanation:
step one:
The total bill was $45.
michelle pays 35% of the total bill 
= 35/100*45
=0.35*45
=$15.75
lori pays 48% of the bill 
= 48/100*45
=0.48*45
=$21.6
Therefore patti will pay
=45-15.75-21.6
=$7.65
 
        
                    
             
        
        
        
Answer:
Yes
Step-by-step explanation:
To figure out if (1,2) is a solution to the system, we can plug the values in and see if it is true.
3x-2y=-1
3(1)-2(2)=-1
3-4=-1
-1=-1
It is true for this equation. Now let's check the next one.
y=-x+3
2=-(1)+3
2=2
Since both equations are true when we plug the values in, (1,2) is a solution to the system.
 
        
                    
             
        
        
        
Answer:
x + y = 11
10x + 5y = 80
Step-by-step explanation:
 
        
             
        
        
        
Answer:
D but see below.
Step-by-step explanation:
It can be factored if you are allowed to use square roots.
(p + 5√5)(p - 5√5)
Usually, you are not allowed to do that. Usually you must be working with whole numbers or rational well behaved fractions.
I think, given the above comment, the answer is D