Maths Olympiad Prep

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Algebra Difficulty 2.4 Junior Find the answer Canada

A line intersects the positive xx-axis and positive yy-axis, as shown.

A possible equation of this line is

Pick one

Solution

We consider the equation of the line shown in the form y=mx+by=mx+b.

The slope, mm, of the line shown is negative.

The yy-intercept, bb, of the line shown is positive.

Of the given choices only y=2x+3y=-2x+3 has m<0m<0 and b>0b>0.

Therefore, a possible equation for the line is y=2x+3y=-2x+3.

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Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.