Isosceles Right Triangle (missing sides)

Me answer number 3plz explain how you do it

Find the equation of the line that goes through the points (4, –1) and (2, –5). use slope formula, equation, to find the slope of a line that passes through the points. m = use slope-intercept form, y = mx + b, to find the y-intercept (b) of the line. b = write the equation in slope-intercept form, y = mx + b.

If i have 20$ and i gave 5$ away how much i got