Question

Зная, что x+3y=8 найдите ( 2x - 6y ) : ( 0,25x 2 -2,25y 2 ) .

Answer 1

$frac{ ( 2x - 6y ) }{ ( 0,25x^ 2 -2,25y^ 2 )}= frac{2(x-3y)}{0.25(x^2-9y^2)} = frac{2(x-3y)}{0.25(x-3y)(x+3y)}= frac{2}{0.25(x+3y)} = \ \ = frac{2}{0.25*8} = frac{2}{2} =1$