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Write the equation of the line if the line passes through (4,4) and the y-intercept is -4.

•y = 2x - 4
•y = 2x - 2
•None of these answers are correct.
•y = 8x + 4
•y = 2x + 4

1 Answer

5 votes

Answer:

y = 2*x - 4

Explanation:

The general equation for a line is:

y = a*x + b

Where a is the slope and b is the y-intercept.

In this case, we know that the line passes through (4, 4) and the y-intercept is -4.

Then:

b = -4

So our line is something like:

y = a*x - 4

Now, we know that the line passes through (4, 4), which means that when x = 4, y = 4.

If we replace these values in the equation, we get:

4 = a*4 - 4

Now we can solve this for a.

4 = a*4 - 4

4 + 4 = a*4

8 = a*4

8/4 = a = 2

Then the equation for the line is:

y = 2*x - 4

User Gary Vernon Grubb
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