Question 391559
Are y=2x+9 and 2x+4y=10 parallel, perpendicular,or neither?
y=2x+9 ......................1
2x+4y=10 
4y= -2x+10
/4
y = -2/4 x +5
y = (-1/2)x +5................2
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The slope of first equation is 2
the slope of second equation is (-1/2)
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m1 * m2 = 2 * (-1/2) = -1
so the lines are perpendicular.
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{{{ graph(300,300,-10,10,-10,10,(2x+9),(-x/2 + 5))}}}