The slope of line AB is slope = (change in y)/(change in x) slope = (14 -(-3))/(7 -(-10)) = 17/17 = 1
The slope of line CD is the negative reciprocal of that, -1/1 = -1. The point-slope form of the equation for line CD can be written as y = -1(x -5) +12 y = -x +17
The x-intercept is the value of x when y = 0. 0 = -x +17 x = 17 The x-intercept is ... (17, 0)
Another way to write the equation for line CD is "standard form." For this, we add x to the slope-intercept form to get ... x + y = 17
For the second part of your question, we can find the answer by adding the x- and y-coordinates to see which sum is 17. -5 +24 = 19 -2 +19 = 17 . . . . . . . . . the point (-2, 19) is the correct choice 7 +(-10) = -3 8 +11 = 19
