Answer:
or
Step-by-step explanation:
-7,-3,1,5,... is a arithmetic sequence.
Arithmetic sequences have a common difference. That is, it is going up by 4 each time.
When you see arithmetic sequence, you should think linear equation.
The point-slope form of a line is 
.
m is the common difference, the slope.
Any they are using the point at x=1 in the point slope form. So they are using (1,-7).
So let's put this into our point-slope form:
Subtract 7 on both sides:
So your answer is
Domain is x values... Y is y values
Any equation that has a slope of 1/2. The equation has to be equivalent to y=1/2x-3 so, you can use the equation y=1/2x+4 (for example)
This is a system of equation:
7y - 5x = 31
x = 4 - 2y
Plug in 4 - 2y for x
7y - 5(4 - 2y) = 31
Distribute -5 to both 4 and -2y
7y - 20 + 10y = 31
Simplify
17y - 20 = 31
Isolate the y. Note the equal sign. What you do to one side you do to the other. Do the opposite of PEMDAS.
Add 20 to both sides
17y - 20 (+20) = 31 (+20)
17y = 51
Divide 17 from both sides to isolate the y
17y/17 = 51/17
y = 51/17 or 3
y = 3
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Plug in 3 for y in one of the equations.
x=4−2y
x = 4 - 2(3)
Simplify.
x = 4 - 6
x = -2
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x = -2, y = 3 is your answer, or B)
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hope this helps
