Question

A line includes the points (1,9) and (4,24). What is the equation in slope-intercept form?

Answer 1

y = 5x+4

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Explanation:

The slope-intercept form of an equation is like this:

• y= mx+b

M stands for the slope and b for the y-intercept.

First, we need to find the slope:

• m= slope= y1-y2/ x1-x2

• m= slope= 9-24/1-4

• m= 5

Now we know: y= 5x+b

Now, to find b we have to choose one of your points. Let's use the first given point: (1, 9)

With the slope-intercept form equation I showed before, substitute x and y with the values of one point.

• 9= 5(1)+b
• 9= 5+b
• 9- 5= 5-5+b
• 4= b

Substitute the b in the equation, and that's your answer:

• y= 5x+4