Toán 2x(x + 3) – 6x(x – 4) = 0 10x(5x – 5) – 7(3x – 2) = 4 17/07/2021 By Samantha 2x(x + 3) – 6x(x – 4) = 0 10x(5x – 5) – 7(3x – 2) = 4
Đáp án: Giải thích các bước giải: `2x(x + 3) – 6x(x – 4) = 0` `⇔ 2x^2+6x-6x^2+24x=0` `⇔ -3x^2+30x=0` `⇔ 3x(x-10)=0` `⇔` \(\left[ \begin{array}{l}x=0\\x=10\end{array} \right.\) Vậy `S={0;10}` `10x(5x – 5) – 7(3x – 2) = 4` `⇔ 50x^2-50x-21x+14=4` `⇔ 50x^2-71x+10=0` `⇔` \(\left[ \begin{array}{l}x \approx 1,26\\x \approx 0,16\end{array} \right.\) Trả lời
Đáp án:
Giải thích các bước giải:
`2x(x + 3) – 6x(x – 4) = 0`
`⇔ 2x^2+6x-6x^2+24x=0`
`⇔ -3x^2+30x=0`
`⇔ 3x(x-10)=0`
`⇔` \(\left[ \begin{array}{l}x=0\\x=10\end{array} \right.\)
Vậy `S={0;10}`
`10x(5x – 5) – 7(3x – 2) = 4`
`⇔ 50x^2-50x-21x+14=4`
`⇔ 50x^2-71x+10=0`
`⇔` \(\left[ \begin{array}{l}x \approx 1,26\\x \approx 0,16\end{array} \right.\)