Which is not an equation of the line that passes through the points (1, 1) and (5, 5)?
y - x = 0
x - y = 0
-x - y = 0
None of the above

Solution:

The equation to find the slope is

m = (y₂ - y₁) / (x₂ - x₁)

The points given are (1, 1) and (5, 5)

Substituting the values in the formula

m = (5 - 1)/(5 - 1)

m = 4/4

m = 1

Let us take the slope m = 1 and the point (1, 1)

y - y₁ = m (x - x₁)

Substituting the values

y - 1 = 1 (x - 1)

y - 1 = x - 1

y = x

We can write it as,

y - x = 0

By subtracting on both sides we get,

x - y = 0

Therefore, - x - y = 0 is not the equation of the line.

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Which is not an equation of the line that passes through the points (1, 1) and (5, 5)?

Summary:

- x - y = 0 is not an equation of the line that passes through the points (1, 1) and (5, 5).