Đáp án:
`S={-1/12}`
Giải thích các bước giải:
`(7x^2-14x-5)/15=(2x+1)^2/5-(x-1)^2/3`
`<=>(7x^2-14x-5)/15=(3(2x+1)^2)/15-(5(x-1)^2)/15`
`<=>7x^2-14x-5=3(2x+1)^2-5(x-1)^2`
`<=>7x^2-14x-5=3(4x^2+4x+1)-5(x^2-2x+1)`
`<=>7x^2-14x-5=12x^2+12x+3-5x^2+10x-5`
`<=>7x^2-14x-5=7x^2+22x-2`
`<=>-36x=3`
`<=>x=-1/12`
Vậy phương trình có tập nghiệm `S={-1/12}`
Đáp án:Giải thích các bước giải:
$\dfrac{(2+1)^{2}}{5}-$ $\dfrac{(x-1)^{2}}{y}=$ $\dfrac{7x^{2}-14x-5}{5}$
$⇔3(2x+1)^{2}-5($ $x-1)^{2}=$ $7x^{2}-14x-5$
$\text{⇔ }$ $12x^{2}+12x+3-$ $5x^{2}+10x-5-$ $7x^{2}+14x+5=0$
$\text{⇔ 36x + 3 = 0 }$
$\text{⇔ 3 ( 12x + 1 ) = 0 }$
$\text{⇔12x + 1= 0 }$
$⇔x=\dfrac{-1}{12}$
$\text{This is the homework of chanhannho9509 . }$
Vẽ nhân vật trong thanh gươm diệt quỷ tranh cũ cũ được
Giải nhanh và đúng giúp mình nha mình vote 5 sao
vẽ anime và ngoài ra phải kể những nét vẽ mà bạn rất thích của những dân vẽ không nổi:>
Làm giúp mik vs ạ Hộ mik 2 câu là tốt rồi ạ. Cảm ơn
cho các đại lượng thể tích khối lượng khối lượng riêng trọng lượng trọng lượng riêng hỏi khi đun nóng một chất thì các đại lượng nào không thay đổi các đại lượng nào sẽ thay đổi nếu thay đổi thì tăng hay giảm
Giải giúp mình bài 1 hình , cần gấp lấm ạ
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1. Somebody cuts the grass every day 2. Someone delivers milk in the morning 3. The boy is eating the cake 4. Jane is singing a new song 5. My sister cooks meals every day 6. My brother uses a pencil to draw beahtiful pictures. 7. My father is painting our house 8. We are reading novels right now 9. The waiter brings me this dish 10. Our friends send these postcards to us Giúp mình chuyển các câu trên sang câu bị động với ạ
Giải giúp em với ạ @@@@@@@@@@@@@@
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