(-4 - 3)(1 - (3 + 5)) × 5
(-7)(-1 - 2) × 5
(-7)(-3) × 5
21 × 5
105
        
             
        
        
        
Answer:
(-2, -4)
Step-by-step explanation:
–2x + 2y = -4
3х + Зу = -18
Divide the first equation by 2
–2x/2 + 2y/2 = -4/2
-x +y = -2
Divide the second equation by 3
3х/3 + Зу/3 = -18/3
x + y = -6
Add these equation together
-x +y = -2
x + y = -6
-------------------
0x + 2y = -8
2y = -8
Divide each side by 2
2y/2 = -8/2
y = -4
Now we need x
x+y = -6
x-4 = -6
Add 4 to each side 
x-4+4 = -6+4
x = -2
 
        
             
        
        
        
<h3>Option C</h3><h3>The average rate of the reaction over the entire course of the reaction is: 

</h3>
<em><u>Solution:</u></em>
Average rate is the ratio of concentration change to the time taken for the change

The concentration of the reactants changes 1.8 M to 0.6 M 
here, the time interval given is 0 to 580 sec
Therefore,

Thus option C is correct
 
        
        
        
we know that
If the point has an nonzero abscissa (x coordinate) then it can be located in any of the four quadrants
If the point has an negative ordinate (y coordinate) then it can be located in Quadrant III or Quadrant IV
therefore
the answer is the option
Quadrant III or Quadrant IV
 
        
             
        
        
        
Given:
The height h of an object after t seconds is

The height of a neighboring 50-foot tall building is modeled by the equation h=50.
The time (t) when the object will be at the same height as the building is found to be t = –2 and t = 5. 
To find:
The statement which describes the validity of these solutions.
Solution:
We have,

Here, t is the time in seconds.
For t=-2,



For t=5,



So, the value of h is 50 at t=-2 and t=5.
We know that time is always positive so it cannot be negative value. It means t=-2 is not possible.
The solution t = 5 is the only valid solution to this system since time cannot be negative.
Therefore, the correct option is C.