Answer: C) 5
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x = independent variable, y = dependent variable
Assuming this is a linear function, each increase of x by 2 leads to y going up by 10. So 10/2 = 5 is the unit increase each time x bumps up by 1.
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An alternative is to use the slope formula to get
m = (y2 - y1)/(x2 - x1)
m = (25 - 15)/(4 - 2)
m = 10/2 <--- this expression shows up again
m = 5 <---- leading to the same answer as before
So we see that the slope formula is a more drawn out method to finding the answer.
Answer:

Step-by-step explanation:
we have
<em>The equation of the first line</em>
------> equation A
<em>The equation of the second line</em>
------> equation B
Solve the system of equations by elimination
Multiply equation A by -4 both sides
--------> equation C
Adds equation B and equation C

<em>Find the value of x</em>
substitute the value of y


Multiply by 3 both sides


therefore
The solution to the system of equations is the point 