Firstly, let's factorise each equation individually - to do this, find 2 numbers that when summed add to the value of the second term, and when multiplied give the value of the third term.
7 and 12 give us 4 and 3 (4+3=7, 4*3=12) -- 8 and 15 give us 5 and 3 (5+3=8, 5*3=15)
Now we can rewrite these equations as (y+4)(y+3) and (y+5)(y+3) respectively.
Putting this in a fraction: (y+4)(y+3)/(y+5)(y+3) -- We can clearly see that there is a y+3 on both sides of the fraction, and given there are no terms outside of the brackets being multiplied, we can directly cancel.
This gives us our final answer:
(y+4)/(y+5)
        
             
        
        
        
Answer:
52%
Step-by-step explanation:
52 out of 100 is the same as .52, when you put that as a percentage, you get 52%
 
        
                    
             
        
        
        
Answer:
 The function y = -x whose reflection in the line y =x is itself.
Step-by-step explanation:
A reflection that maps every point of a figure to an image across a fixed line. Then the fixed line is called the line of reflection.
The reflection of the point (x,y)  in the line y = x is the point (y, x).
Therefore, the  function y = -x  whose  reflection in the line y =x is itself.
Symmetries of the function f(x)= -x is:     
A function symmetric with respect to the y-axis is called an even function.
If f(-x) = f(x)
A function that is symmetric with respect to the origin is called an odd function.
if f(-x) = -f(x)
then, we must look at f(-x);
f(x) = -x
f(-x)= -(-x)= x = -f(x)
this function is symmetrical to with respect to origin. 
Therefore, this function is an odd function.