3u ^ { 2} - 5d \div 5= 0
3u^2-(5d)/5=0
color(red)("Simplifying:")
3u^2-d=0
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color(green)("SOLVING FOR 'd':")
color(red)("Rearrange equation to isolate d:")
therefore d=3u^2
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color(green)("SOLVING FOR 'u':")
3u^2=d
color(red)("Divide both sides by 3:")
u^2=d/3
color(red)("Take square root of both sides:")
therefore u=+-sqrt(d/3)