Line \(k\) is in the rectangular coordinate system. If line

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Line k is in the rectangular coordinate system. If line k is defined by the equation 3y = 2x + 6, and line k intersects the x-axis at point (a,b), then what is the value of a?

A. -3
B. -2
C. 0
D. 2
E. 3

The OA is A

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by Ian Stewart » Sat Jul 06, 2019 4:14 am
If (a, b) is on the x-axis, then b is zero. So the line intersects the x-axis at (a, 0), and if (a, 0) is on the line, that point must 'work' in the line's equation. Plugging in x=a and y=0 we get

3(0) = 2(a) + 6
2a = -6
a = -3
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