Решение
x + y = 40
x*y = 364
y = 40 - x
x*(40 -x) = 364
x∧2 - 40x + 364 = 0
D = (40∧2 - 4*1*364 = 1600 - 1456 = 144
x1 = (40 - 12) / 2 = 14
x2 = (40 + 12) / 2 = 26
y1 = 40 - 14 = 26
y2 = 40 - 26 14
Ответ: (14; 26); (26;14)
( 5 - 6a ) / 3a - ( 1 - 2b ) / b = ( b( 5 - 6a ) - 3a( 1 - 2b )) / 3ab = ( 5b - 6ab - 3a + 6ab ) / 3ab = ( 5b - 3a ) / 3ab
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12x^2 / ( 5x - 10 ) * ( x - 2 ) / 18x = ( 6x*2x ) / ( 5( x - 2 )) * ( x - 2 ) / ( 6x*3 ) =
= 2x / 15 = 2/15x
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( a - b ) : (( a^2 - b^2 ) / 3a^2 ) = ( a - b ) : ( ( a - b )( a + b ) / 3a^2 ) =
= 3a^2 / ( a + b )