Answer: y=x-20
Explanation:
(90,70) will be x1,y2. (30,10) will be x1,y1. Put these values into the slope formula, which is y2-y1/x2-x1. 70-10/90-30. 60/60=1. The slope is 1. Now to find the slope-intercept equation, use point slope form which is y-y1=m(x-x1). y-10=1(x-30). Distribute the 1 to the terms in the parenthesis. y-10=x-30. Add 10 to both sides to eliminate 10. y-10+10=x-30+10. y=x-20.