Question

A line has unit slope and passes through point origin (0,0) . What is the equation of the line?The answer options are:

a. y = 0
c. y = -xB) x = 0
d. y = x

Answer 1

The answer is: [D]: " y = x " .
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Note: The "slope-intercept form" of a line is in written in the following format:
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" y = mx + b " ;
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in which:
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"y" is "isolated as a single variable" on the left-hand side of the equation the equation;
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"m" is the slope of the line;
and is the coefficient of "x" ;
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"b" is the "y-intercept" of the line;
that is, "b" is the "x-coordinate" of the point
on the line of the equation at which "y = 0" ;
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We are given: "a unit slope" ; that is: a slope of "1" ;

So, " m = 1 " ;
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and that the line passes through the point: " (0, 0) " .
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So, " b = 0 " ;
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So, we can write this as: "y = 1x + 0 " ;

As a practical matter —and by convention — we can eliminate the "+ 0" ; and we have:
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" y = 1x " ; and long the same guidelines; we can write as:
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" y = x " ; which is: Answer choice: [D] .
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