If the coordinates of point a are (8, 0) and the coordinates of point b are (3, 7), the y-intercept of is . if the coordinates of point d are (5, 5), the equation of line is y = x + . nextreset

Line ab is y = -7/5x + 56/5i don't understand  where point d comes into this. 

Look, when you want to do something like put it like x^2. x2 could mean x² or x₂. so to clear confusion, know the notation. to find the product multiply the x's and you get -8x and the y's and you get 6y. since it's all being multiplied it is just -8x6y, or answer a. although the better answer is -48xy(combining -8 and 6) because you should multiply constants whenever you can.