Alright, 
you will need to solve for each variable to find if they got the equation correctly or not.. 
Let's start with h 
isolate h 
(1/2)h = A/(b1+b2)
Now we need to get rid of 1/2 we may do so by multiplying both sides by 2 
h = 2(A/(b1+b2))
And that's not how they did it for h so Option D doesn't apply 
Let's see C
Also doesn't apply since they multiplied 2 only by A rather than A/h
Let's see B
Also not correct they made the same mistake as with option C
Let's see A
again same mistake 
when multiplying both sides by 2 
the 2 should be as following 

I believe you should contact your instructor and explain that non of the options is right. 
 
        
             
        
        
        
Slope of  2y = x + 5:-
This is y = 0.5 x + 2.5  in slope intercept form so its slope = 0.5
Slope of the line perpendicular to it = -1 / 0.5 = -2
it passes through (2 , 1) so we have
y- 1 = -2(x - 2)
y = -2x + 4 + 1
The answer is y = -2x + 5
        
             
        
        
        
Answer:
I would help you but I can't read the question.
Step-by-step explanation:
 
        
             
        
        
        
It's 2 sir/ Maam Your Welcome
        
             
        
        
        
Me. Gregory's class has the greatest ratio of boys to students.