You want to try and get rid of one of the variables ( x or y) so you would multiply the second equation by 2 which would make the x variable -2x which then when added to the first equation would eliminate the x variable.
Answer: c. Multiply the second equation by 2.
 
        
             
        
        
        
20 I think! 
Look it up just to be sure
        
                    
             
        
        
        
Answer:

Step-by-step explanation:
we know that
In the right triangle ABC
The function sine of angle 68 degrees is equal to divide the opposite side SB by the hypotenuse AC
so

substitute the values and solve for AC



 
        
             
        
        
        
1
When the input is 0 (horizontal axis), the output is 1 (vertical axis).