Answer:
x = 9, Angles are 54°
Step-by-step explanation:
First, we need to find x:
7x-9 = 5x+9
 +9 +9
7x = 5x+18
-5x -5x
2x = 18
x = 9
Now, we plug our x value in to find our angles.
5(9) + 9 = 54
Angle B = 54°
7(9) - 9 = 54°
Angle E = 54°
(angles are the same due to AAA property)
 
        
             
        
        
        
Answer:
boys = 705
girls = 783
Step-by-step explanation:
We are to find the number of boys and girls in the school 
the answer can be determined using simultaneous equation 
x = boys
y = girls
y - x = 78  equation 1
y + x  = 1488 equation 2 
subtract equation 1 from 2
2x = 1410
x = 1410/2 = 705
Substitute for x in equation 1 
y - 705 = 78
y = 705 + 78 = 783
 
        
             
        
        
        
Answer:
0
Step-by-step explanation:
 
        
             
        
        
        
X=7. 
9x-7y=63
9x-7 x 0=63
9x - 0=63
9x=63
X=7. 
Y=-9
9 x 0 -7y=63