Помогите матем номер 877

Question

Помогите матем номер 877

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Answer 1

1) 5(3-2y)-4(9-y)=3(y+5)
15-10y-36+4y=3y+15
15-10y-36+4y-3y-15=0
-9y-36=0
-9y=36
-y=36/9
-y=4
y=-4

2) 14(2x-3)-5(x+4)=2(3x+5)+5x
28x-42-5x-20=6x+10+5x
28x-42-5x-20-6x-10-5x=0
18x-72=0
18x=72
x=72/18
x=4

Comments

остальные ????

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3)9(3x-7)+3(8x-11)=3(9x+8)
27x-63+24x-33=27x+24
27x-63+24x-33-27x-24=0
24x-120=0
24x=120
x=120/24
x=5