<em>205:(у-27)=41
у-27=205:41
у-27= 5
у=5+27
у=32
</em>
X³ - 64x = x * ( x² - 64 ) = x * ( x - 8 ) * ( x + 8 )
3x ² - 75y² = 3 * ( x² - 25y² ) = 3 * ( x - 5 ) * ( x + 5 )
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y³ + 9y = 0
y * ( y + 9 ) = 0
y = 0
y + 9 = 0 ; y = - 9
Ответ 0 ; - 9
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( x + 3 )² - 49 = 0
( x + 3 - 7 )*( x + 3 + 7 ) = 0
( x - 4 )*( x + 10 ) = 0
x- 4 = 0 ; x = 4
x + 10 = 0 ; x = - 10
Ответ 4 ; - 10
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( y - 4 )² - ( y + 3 )² = 0
( y - 4 - ( y + 3 )) *( y - 4 + ( y + 3 ) ) = 0
( y - 4 - y - 3 )*( y - 4 + y + 3 ) = 0
- 7 * ( 2y - 1 ) = 0
2y - 1 = 0 ; 2y = 1 ; y = 0,5
Ответ 0,5
А) 4/5=3/4x
16x=15
x=15/16
б) 8/9=1/2x
16x=9
x=9/16
в) 27/40=18x/25
40*18x=25*27
720x=675
x= 675/720= 135/144
г) x/4.5=2.1/0.63
0.63x=4.5*2.1
0.63x= 9.45
x=15