1) \(\frac{2x+3}{6}=\frac{7x-3}{-5}\)
\(-5\left(2x+3\right)=6\left(7x-3\right)\)
\(-10x-15=42x-18\)
\(52x=3\)
\(x=\frac{3}{52}\)
2) \(\frac{12-7x}{-13}=\frac{4-3x}{-5}\)
\(-5\left(12-7x\right)=-13\left(4-3x\right)\)
\(-60+35x=-52+39x\)
\(39x-35x=-60+52\)
\(4x=-8\)
\(x=-2\)
Tìm x:\(a,\frac{6x-5}{-7}=\frac{5x-3}{-5}\\ b,\frac{12-7x}{-13}=\frac{4-3x}{-5}\\ c,\frac{2x+4}{7}=\frac{4x-2}{15}\)
Tìm x, biết
1.\(\frac{2x+4}{7}=\frac{4x-2}{15}\)
2. \(\frac{12-7x}{-13}=\frac{4-3x}{-5}\)
3. \(\frac{11x-2}{7x+5}=\frac{11}{8}\)
1 Tìm x:
( \(3x-2\frac{1}{3}\)):( \(3\frac{1}{4}-5\frac{2}{3}+1\frac{4}{5}\)) = \(2-1\frac{1}{3}x\)
2. Tìm x:
\(\frac{x+\frac{2\left(3-x\right)}{5}}{14}-\frac{5x-4\left(x-1\right)}{24}=\frac{7x+2+\frac{9-3x}{5}}{12}+\frac{2}{3}\)
3. Tìm x:
\(\left(1+3x\right)^2-3x\left(2x+6\right)=\left(4-3x\right)\left(x+3\right)-\left(2x-1\right)^2\)
Tìm x, biết
1) \(\frac{x-1}{x-5}=\frac{6}{7}\) 2) \(\frac{x-1}{3}=\frac{x+3}{5}\)
3) \(\frac{3}{7}=\frac{2x+1}{3x+5}\) 4) \(\frac{2x+3}{3x+1}=\frac{3}{4}\)
5) \(\frac{2x+3}{6}=\frac{7x-3}{15}\)
6) \(\frac{6x-5}{-7}=\frac{5x-3}{-5}\)
1.Tìm x :
a)1 - 7x = 3x - 4
2.Tính
a)-2013 . 2028 + 4028 . 26
b)\(\left(\frac{1515}{1616}+\frac{10}{170}\right)-\left(\frac{150}{160}-\frac{16}{17}\right)\)
c)\(\frac{1}{3^1}+\frac{1}{3^2}+\frac{1}{3^3}+...\frac{1}{3^{99}}\)
d)\(\frac{5}{17}+\frac{-4}{7}-\frac{20}{31}+\frac{12}{17}-\frac{11}{31}\)
e)\(\frac{155-\frac{10}{7}-\frac{5}{11}+\frac{5}{23}}{403-\frac{20}{7}-\frac{13}{13}_{ }+\frac{13}{23}}\)
1) a) Tìm x,y:
\(\frac{7x-5}{6}=\frac{6y-4}{4}=\frac{7x+6y-9}{2x}\)
b) Tìm a,b:
\(\frac{a-8}{4}=\frac{b-10}{5}=\frac{c-12}{6}\) và \(3a+2b-c=80\)
tìm x,y,z biết
3x=2y ; 7x=5z, x-y+z=32
\(\frac{2x}{3}=\frac{3y}{4}=\frac{4z}{5}\) và x+y+z=49
\(\frac{x-1}{2}=\frac{y-2}{3}=\frac{z-4}{4}\) và 2x+3y-z=50
tìm x :
\(a.\frac{2}{3x}-\frac{3}{12}=\frac{4}{5}\left(\frac{7}{x}-2\right)\)
\(b.\frac{1}{x-1}+\frac{-2}{3}=\frac{5-3x}{6}-\frac{1}{3}\)
\(c.3-\frac{2}{2x-3}=\frac{2}{5}+\frac{2}{9-6x}-\frac{3}{2}\)
\(d.\frac{x}{2}-\frac{1}{x}=\frac{1}{12}\)
\(e.x^2-\frac{7}{6}x+\frac{1}{3}=0\)
\(l.\frac{13}{x-1}+\frac{5}{2x-2}-\frac{6}{3x-3}\)
Tính bằng cách hợp lí:
a) \(\frac{15}{12}+\frac{5}{13}-\frac{3}{12}-\frac{18}{13}\) ( Phép này tính bằng 1 nhưng lại sai mất)
b) \(\frac{13}{25}+\frac{6}{41}-\frac{38}{25}+\frac{35}{41}-\frac{1}{2}\)
c) \(\left(\frac{1}{2}-\frac{2}{3}\right)-\left(\frac{5}{3}-\frac{3}{2}\right)+\left(\frac{7}{3}-\frac{5}{2}\right)\)
Help me!!!!! Nhanh nhé, 15' thui
