1)1,5(2х-30)=x+5
3x-45-x=5
2x=50
x=25 кг
2) 1+x-1=2x-2
x+x-1+2x-2=15
4х-3=15
4х=18
х=4,5 т
3)8x=5(x+6)
8x=5x+30
8x-5x=30
3x=30
x=10
X + y = z + 1
z - y = 3
X = 2y
Решение
2у + у = z + 1
3y = z + 1 ==> z = 3y - 1
z - y = 3
3y - 1 - y = 3
2y = 4
y = 2
X = 2 • 2 = 4
Z = 3 + y
Z = 3 + 2 = 5
Ответ ( 4 ; 2 ; 5 )
√ X + √ Y = 5
3 √ X - √ Y = 12
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√ X = A ; A > 0
√ Y = B ; B > 0
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A + B = 5
3A - B = 12
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4A = 17
A = 4,25
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4,25 + B = 5
B = 0,75
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√ X = A
√ X = 4,25
X = 18,0625
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√ Y = B
√ Y = 0,75
Y = 0,5625
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Ответ ( 18,0625 ; 0,5625 )
Log₂x-3logx2²=log₂x-6logx2=log₂x-6/log₂x=1
y=<span>log₂x x>0
y</span>²-y-6=0
y=3 y=-2
log₂x=3 x=2³=8
log₂x=-2 x=2⁻²=1/4=0,25
We know that -1≤sin x≤1
2sin x=5
sin x=2.5 and it's not true.
So the answer will be ∅