Answer:
(a) Along the xy-plane, 
7x + 6y = 0
(b) Along the yz-plan,
2y - 3z = 0
(c) Along the xz-plane,
7x - 3z = 0
Step-by-step explanation:
To describe the given set. 
Given the plane (7, 6, -3),
We have the equation as
7x + 6y - 3z = 0
(a) Along the xy-plane, z = 0, and we have
7x + 6y = 0
(b) Along the yz-plan, x = 0, and we have
6y - 3z = 0
Or
2y - 3z = 0
(c) Along the xz-plane, y = 0, and we have
7x - 3z = 0
 
        
             
        
        
        
 2.5 years = 30 months
7500$ in 30 months
x$ in 1 month
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x = (7500*1)/30 = 250
The answer is 250$/month.
 
        
                    
             
        
        
        
Y = 2
y = 4x - 10
2 = 4x - 10
2 + 10 = 4x
12 = 4x
12/4 = x
3 = x
solution is : (3,2)