Giúp mình bài này:
\(\dfrac{24}{17}\) x ( -0,875 + 45% ) - 2\(\dfrac{1}{5}\)
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a) \(\dfrac{2x+3}{24}=\dfrac{3x-1}{32}\)
\(\Rightarrow32\left(2x+3\right)=24\left(3x-1\right)\)
\(\Rightarrow64x+96=72x-24\)
\(\Rightarrow8x=120\Rightarrow x=15\)
b) \(\dfrac{13x-2}{2x+5}=\dfrac{76}{17}\)
\(\Rightarrow17\left(13x-2\right)=76\left(2x+5\right)\)
\(\Rightarrow221x-34=152x+380\)
\(\Rightarrow69x=414\Rightarrow x=6\)
\(E=\dfrac{98:\left(\dfrac{4}{5}\cdot\dfrac{5}{4}\right)}{\dfrac{16}{25}-\dfrac{1}{25}}+\dfrac{\left(\dfrac{27}{25}-\dfrac{2}{25}\right)\cdot\dfrac{7}{4}}{\left(\dfrac{59}{9}-\dfrac{13}{4}\right)\cdot\dfrac{36}{17}}\\ E=\dfrac{98}{\dfrac{3}{5}}+\dfrac{\dfrac{7}{4}}{\dfrac{119}{36}\cdot\dfrac{36}{17}}\\ E=\dfrac{490}{3}+\dfrac{\dfrac{7}{4}}{7}=\dfrac{490}{3}+\dfrac{1}{4}=\dfrac{1963}{12}\)
bạn ơi chỗ kia mik nhìn hơi loạn tí bạn giải thích giúp mik với
Bài 2
b, `\sqrt{3x^2}=x+2` ĐKXĐ : `x>=0`
`=>(\sqrt{3x^2})^2=(x+2)^2`
`=>3x^2=x^2+4x+4`
`=>3x^2-x^2-4x-4=0`
`=>2x^2-4x-4=0`
`=>x^2-2x-2=0`
`=>(x^2-2x+1)-3=0`
`=>(x-1)^2=3`
`=>(x-1)^2=(\pm \sqrt{3})^2`
`=>` $\left[\begin{matrix} x-1=\sqrt{3}\\ x-1=-\sqrt{3}\end{matrix}\right.$
`=>` $\left[\begin{matrix} x=1+\sqrt{3}\\ x=1-\sqrt{3}\end{matrix}\right.$
Vậy `S={1+\sqrt{3};1-\sqrt{3}}`
\(\dfrac{-1}{4}< \dfrac{x}{24}< \dfrac{-1}{6}\\ \dfrac{-6}{24}< \dfrac{x}{24}< \dfrac{-4}{24}\\ \Rightarrow x=-5\)
a) Ta có: \(7\cdot\dfrac{3}{14}-\dfrac{1}{14}\)
\(=\dfrac{3}{2}-\dfrac{1}{14}\)
\(=\dfrac{21}{14}-\dfrac{1}{14}\)
\(=\dfrac{10}{7}\)
b) Ta có: \(\dfrac{3}{2}+\dfrac{7}{4}:\dfrac{5}{2}\)
\(=\dfrac{3}{2}+\dfrac{7}{4}\cdot\dfrac{2}{5}\)
\(=\dfrac{3}{2}+\dfrac{7}{10}\)
\(=\dfrac{15}{10}+\dfrac{7}{10}=\dfrac{22}{10}=\dfrac{11}{5}\)
Lời giải:
\(7\times \frac{3}{14}-\frac{1}{14}=\frac{7\times 3}{14}-\frac{1}{14}=\frac{21}{14}-\frac{1}{14}=\frac{21-1}{14}=\frac{20}{14}=\frac{2\times 10}{2\times 7}=\frac{10}{7}\)
\(\frac{3}{2}+\frac{7}{4}:\frac{5}{2}=\frac{3}{2}+\frac{7}{4}\times \frac{2}{5}=\frac{3}{2}+\frac{7\times 2}{4\times 5}=\frac{3}{2}+\frac{7\times 2}{2\times 2\times 5}\)
\(=\frac{3}{2}+\frac{7}{2\times 5}=\frac{3\times 5}{2\times 5}+\frac{7}{2\times 5}=\frac{3\times 5+7}{2\times 5}=\frac{22}{2\times 5}=\frac{2\times 11}{2\times 5}=\frac{11}{5}\)
\(\dfrac{25}{2-x}=\dfrac{5}{3}\\ \Rightarrow25.3=5.\left(2-x\right)\\ \Rightarrow75=10-5x\\ \Rightarrow-5x=-65\\ \Rightarrow13\)
\(MSC\left(3;4;24\right)=24\)
⇒ \(\dfrac{1}{3}=\dfrac{1\times8}{3\times8}=\dfrac{8}{24}\)
\(\dfrac{1}{4}=\dfrac{1\times6}{4\times6}=\dfrac{6}{24}\)
\(\dfrac{1}{24}\) ( giữ nguyên phân số )
Câu 1:
\(=\dfrac{15}{34}+\dfrac{19}{34}-1-\dfrac{15}{17}+\dfrac{1}{3}+\dfrac{3}{5}\)
\(=-\dfrac{15}{17}+\dfrac{14}{15}=\dfrac{13}{255}\)
Câu 2:
\(=\dfrac{5^4\cdot5^4\cdot2^8}{4^4\cdot6^4\cdot3^2\cdot5}=\dfrac{5^7}{6^4\cdot3^2}\)
\(\dfrac{24}{17}\left(-0,875+45\%\right)-2\dfrac{1}{5}\)
\(=\dfrac{24}{17}\left(-\dfrac{7}{8}+\dfrac{9}{20}\right)-2,2\)
\(=\dfrac{24}{17}\cdot\dfrac{-7\cdot5+9\cdot2}{40}-2,2\)
\(=\dfrac{24}{40}\cdot\dfrac{-35+18}{17}-2,2\)
\(=-0,6-2,2=-2,8\)