Question

Which of these points lies on the line described by the equation below? y - 8 = 3(x + 6)

a. (-8,6)
b. (-6,8)
c. (6,-8)
d. (8,-6)

Answer 1

y - 8 = 3 (x+ 6)

a). Try (-8, 6)
y - 8 = 3 (x+ 6)
6 - 8 = 3 (-8 + 6)
-2 = 3 (-2)
-2 = -6 No. That doesn't work.

b). Try (-6, 8)
y - 8 = 3 (x + 6)
8 - 8 = 3 (-6 + 6)
0 = 3 ( 0 )
0 = 0 Yes. That works.


c). Try (6, -8)
y - 8 = 3 (x+ 6)
-8 - 8 = 3 (6 + 6)
-16 = 3 (12)
-16 = 36 No. That doesn't work.

d). Try (8, -6)
y - 8 = 3 (x+ 6)
-6 - 8 = 3 (8 + 6)
-14 = 3 (14)
-14 = 42 No. That doesn't work.

Choice (b) is the only point that lies on the line.