The fewest number of expressions is 3.
Answer:
1 and - 1
Step-by-step explanation:
The equation of a line passing through the origin is
y = mx ( m is the slope ( gradient ) )
y = x ← is in this form
with gradient m = 1
Parallel lines have equal gradients
Then the gradients of lines parallel to the given line is 1
Given a line with gradient m then the gradient of a line perpendicular to it is
= - = - = - 1
Then the gradients of lines perpendicular to this line is - 1
The solution to that equation is (6,-4)
You need to see which is more