<PRE><B>Question 583792</B>
5x+4y=12

20x+16y=0

Write both equations in slope-intercept form:

y = (-5/4)x - 3

y = (-20/16)x + 0 = (-5/4)x

y = mx + b

slope, m, is -5/4 for both, so they are parallel

Verify with graph

 {{{ graph( 800, 700, -6, 5, -10, 10, (-5/4)x - 3, (-5/4)x) }}}

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