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a in (-oo:+oo)
a*((-4*a-1)/(-10)) = 3/8 // - 3/8
a*((-4*a-1)/(-10))-(3/8) = 0
a*((-4*a-1)/(-10))-3/8 = 0
(a*(-4*a-1))/(-10)-3/8 = 0
(8*a*(-4*a-1))/(-10*8)+(-10*(-3))/(-10*8) = 0
8*a*(-4*a-1)-10*(-3) = 0
30-32*a^2-8*a = 0
30-32*a^2-8*a = 0
2*(15-16*a^2-4*a) = 0
15-16*a^2-4*a = 0
DELTA = (-4)^2-(-16*4*15)
DELTA = 976
DELTA > 0
a = (976^(1/2)+4)/(-16*2) or a = (4-976^(1/2))/(-16*2)
a = (4*61^(1/2)+4)/(-32) or a = (4-4*61^(1/2))/(-32)
2*(a-((4*61^(1/2)+4)/(-32)))*(a-((4-4*61^(1/2))/(-32))) = 0
(2*(a-((4*61^(1/2)+4)/(-32)))*(a-((4-4*61^(1/2))/(-32))))/(-10*8) = 0
(2*(a-((4*61^(1/2)+4)/(-32)))*(a-((4-4*61^(1/2))/(-32))))/(-10*8) = 0 // * -10*8
2*(a-((4*61^(1/2)+4)/(-32)))*(a-((4-4*61^(1/2))/(-32))) = 0
( a-((4*61^(1/2)+4)/(-32)) )
a-((4*61^(1/2)+4)/(-32)) = 0 // + (4*61^(1/2)+4)/(-32)
a = (4*61^(1/2)+4)/(-32)
( a-((4-4*61^(1/2))/(-32)) )
a-((4-4*61^(1/2))/(-32)) = 0 // + (4-4*61^(1/2))/(-32)
a = (4-4*61^(1/2))/(-32)
a in { (4*61^(1/2)+4)/(-32), (4-4*61^(1/2))/(-32) }
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