Решите уравнения пожалуйста. 1) (x-199)/(x+7)=-5 2) (x-3)/(x+2)=4x 3)...

Question

Решите уравнения пожалуйста.
1) (x-199)/(x+7)=-5
2) (x-3)/(x+2)=4x
3) (2-3x)/(x+5)≥(2x+1)/(x+5)

Answer 1

1) x-199=-5(x+7)
x-199=-5x -35
6x=164
x=27*1/3

Comments

2) x-3=4x(x+2)

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x-3=4x2 + 8x 4x2+7x +3=0 x1=(-7+1)/8=-0/75 x2=(-7-1)/8=-1

Answer 2

1) (x-199)/(x+7)=-5
x-199=-5x-35
x+5x=199-35
6x=164
x=164/6=27 2/6=27 1/3
2) (x-3)/(x+2)=4x
x-3=4x²+8x
4x²+7x+3=0
D=49-48=1
x1=(-7-1)/8=-1
x2=(-7+1)/8=-3/4
3) (2-3x)/(x+5)≥(2x+1)/(x+5)
(2-3x)/(x+5) -(2x+1)/(x+5)≥0
(2-3x-2x-1)/(x-5)≥0
(1-5x)/(x-5)≥0
x=0,2  x=5
       _            +              _
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             0,2            5
x∈[0,2;5)