What is the equation of a line that passes through the point (3,-4) and has a slope of 2?

Expert Answers

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The equation for a line is y = m*x + b, where a point is represented by (x,y), m is the slope, and b is the y intercept (i.e. when x = 0, y = b). So plug in the information from your question, and let's see what we get:

-4 = 2*3 + b   or   b = -4 - 2*3 = -10. So m = 2, and b = -10, thus the equation for the line that passes through the point (3,-4) is:

y = 2x - 10

 

You could also use the slope intercept form of the equation for a line for a point (x1,y1), which is:

y - y1 = m(x - x1) --> y - -4 = 2(x - 3) or,

y + 4 = 2x - 6

y = 2x - 6 - 4

y = 2x - 10

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