Answer:
45x^2-328x+124
Step-by-step explanation:
 
        
             
        
        
        
Answer:
Slope = -7/2
Step-by-step explanation:
The standard equation of a line is expressed as y = mx+c
m is the slope 
c is the y-intercept
Given the equation y = -7/2 x - 5/8
Compare with the general equation
mx = -7/2x
Divide both sides by x
mx/x = -7x/2x
m = -7/2
Hence the slope of the line is -7/2
 
        
             
        
        
        
I'll solve 21, and you then should be able to solve the rest on your own!
Since ADC is 135, that means that that whole angle is 135 degrees. In addition, since angles ADB and BDC add up to ADC, we get ADB+BDC=ADC=135=11x+9+7x=18x+9. Subtracting 9 from both sides, we get 126=18x. Dividing both sides by 18, we get x=7. Plugging that into 11x+9=BDC, we get 11*7+9=77+9=86