As this rectangle has it's sides parallel to x axis and y axis 
 it is easy to find the length of it's sides by counting the number of blocks on each sides.
Let us first find co ordinates of all four points 
 we would calculate them left and right and up down direction from the origian ( the cross point of x and y axis ) 
A : it is 2 unit left 2 unit up ( -2 , +2 )
B is 5 unit right 2 unit up ( +5 ,+2)
C is 5 unit right 2 unit down ( +5,-2)
D is 2 unit left 2 unit down ( -2,-2)
Let us now find the distance AB : A is 2 unit left B is 5 unit right so length AB= 2+5 = 7 
Let us now find distance AD : A is 2 unit up and D is 2 unit down 
 so length AD= 2+2= 4
Answer should be 7 x 4 units 
 
        
                    
             
        
        
        
Both triangles that are given (with right angles) lie in plane m, proving that AC is perpendicular to plane m. As angle acd is from a triangle that shares the common perpendicular, it too is a right angle
 
        
             
        
        
        
I believe it’s 900. Yeah, I think the answer is 900.
        
                    
             
        
        
        
The prime factorization of the numerator, 315, is 5 x 3 x 3 x 7. That of the denominator, 1575 is 5 x 5 x 3 x 3 x 7. To convert the fraction to its lowest form, cancel all the factors that appear to both the numerator and denominator. We will be left with 1/5.