Question 1109234
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1) (6,3) is the midpoint of the line joining the points with coordinate (-4,y) and (x,-6). The value of x+y is: 
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{{{(-4+x)/2=6}}}
{{{x-4=12}}}
{{{x=16}}}
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{{{(y-6)/2=3}}}
{{{y-6=6}}}
{{{y=12}}}
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{{{x+y=16+12}}}
{{{highlight(28)}}}



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3) If two lines 6x-y+5=0 and ax+2y-7=0 are parallel then a equals?
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{{{(6/1)=-(a/2)}}}

{{{6=-a/2}}}

{{{highlight(a=-12)}}}