Use the interactive tool to graph the line given the following information:     coordinates (1,–3)     slope of –2 based on your investigation, what is the value of b for the point (0,b)?

Finding the equation of the line, it is found that the value of b is -1.

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The equation of a line is given by:

In which:

m is the slope.b is the y-intercept.

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Slope of -2 means that , and thus, .It goes through point (1,-3), which means that when . We use this to find b.

The value of b is -1.

A similar problem is given at link

The line can be written in the form y=mx+b. Plugging -2 in for m , 1 in for x, and -3 in for y, we get -3=-2*1+b=-2+b. Adding 2 to both sides, we get b=-1 and our equation turns into y=-2x-1 since y and x stay variables. Plugging it into a graphing calculator, we get in (0,b) that b = -1