We don't need the figure
angle b = 44 degrees
angle a = 62 degrees
angle e = 50 degrees
angle f = unknown
we know that 
angle a + b + e + f = 180 degrees
50 + 44 + 62 + f =180 degrees
f= 180-50-44-62
but here there is only one blank so we have to add 44 and 62 to make one number that is 106
therefore, f = 180-50-106
if you further want to solve it angle f is 24
        
             
        
        
        
To find the slope you use the slope formula y2-y1 / x2-x1. So use two point on the line we will make ours (1,2) and (3,4). Substitute to make 4-2 / 3-1 = 1/1 so using the rise over run method. The line rises up one and runs by one. The slash mark means divide, it's easiest in a fraction. 
Also if you come across the equation y=mx+b, m is the slope and b is the y-intercept, this is called slope intercept formula.
        
             
        
        
        
12.5% goes to .125
so .125 as a fraction is: 
 
 
        
        
        
<u>Answer:</u>
x=3
<u>Step-by-step explanation:</u>
3(3 + x)=15+x
<u>distribute</u>
9 + 3x=  15+x
<u>subtract x from each side</u>
9+3x-x = 15
9+2x = 15
<u>subtract 9 from each side</u>
9+2x-9 = 15-9
2x = 6
<u>divide by 2</u>
2x/2 = 6/2
x=3