Indicate in standard form the equation of the line passing through the given points.

s(1/2, 1), t(1/2, 4)

x = ?

The equation of the line given two points may be expressed as,
                                y - y1 = ((y2 - y1) / (x2 - x1))(x - x1)
Substituting the known values,
                               y - 1 = ((4 - 1) / (0.5 - 0.5))(x - 0.5)
The denominator of the slope of the line is 0, making the slope undefined. The line is therefore vertical and its equation is x = 1/2. 

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