1) Use the slope formula, , and the given points to find the slope. and represent the x and y values of one point the line must intersect, and and represent the x and y values of another point the line must also intersect:
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2) Using the point-slope formula, , use the slope you just calculated and substitute it for m. Choose any of the two points given (I chose (1,8)) and substitute its x and y values for and . Don't worry, the equation of the line is the same no matter which point you choose (unless the question specifies which one you need to choose):
We first solve to find the slope. The slope of the line is 5/3. Then we substitute that into the formula that is y-y1=m(x-x1). M represents the slope of the line and the x and y’s represent the point values. So we get 8-3=5/3(1+2). We get this solution if it asks you to figure out the slope along the way too.
If they ask you the equation when knowing only the two points you do 8-3=m(1+3)
They both mean the same thing ( it just depends on what the problem is specifically asking you about)