use slopes to show that the triangle with vertices

(-2,7), (6,9) and (3,4) is a right triangle.

write an equation of the line that has y-intercept 5/7 and is parallel to the graph of 6x-3y=1

1 answer

A(-2 , 7) , B(6 , 9).
m1 - (9 - 7) / (6 - (-2)) = 2 / 8 =1/4.

B(6 , 9) , C(3 , 4).
m2 = (4 - 9) / (3 - 6) = -5 / -3 = 5/3.

A(-2 , 7) , C(3 , 4).
m3 = (4 - 7) / (3 - (-2)) =-3 / 5=-3/5.

The slope of BC is the neg. reciprocal of AB. Therefore, the two lines are
perpindicular and form a rt triangle.

m = -A / B = -6 / -3 = 2.
Y = mx + b,
Y = 2x + 5 / 7.