Tìm x, biết
1.\(\frac{2x+4}{7}=\frac{4x-2}{15}\)
2. \(\frac{12-7x}{-13}=\frac{4-3x}{-5}\)
3. \(\frac{11x-2}{7x+5}=\frac{11}{8}\)
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 :
\(a.\frac{7^{x+2}+7^{x+1}+7x}{57}=\frac{5^{2x}+5^{2x+1}+5^{2x+3}}{131}\)
\(b.\left(4x-3\right)^4=\left(4x-3\right)^2\)
\(3,2.\frac{15}{16}-\left(75\%+\frac{2}{7}\right):\left(-1\frac{1}{28}\right)\)
\(\left(0,25+12,5-\frac{5}{16}\right):\left[12-\frac{7}{12}:\left(\frac{3}{8}-\frac{1}{12}\right)\right]\)
\(\left(\frac{-3}{5}+\frac{5}{11}\right):\frac{-3}{7}+\left(\frac{-2}{5}+\frac{6}{5}\right):\frac{-3}{7}\)
\(14,5-\frac{8}{9}:\left(35-34\frac{8}{9}\right).\frac{9}{8}\)
\(1\frac{1}{15}-\left(\frac{1}{15}+\frac{4}{9}:\frac{-2}{3}-\frac{28}{16}.\frac{6}{35}\right)-\frac{3}{10}\)
Tìm x
\(\left(4,5-2x\right)\left(-3\frac{2}{3}\right)=\frac{11}{15}\)
\(\backslash34-x\backslash=\left(-3\right)^4\)
\(\left(4x^2-1\right)\left(\text{\x}\backslash-\frac{2}{3}\right)=0\)
\(\frac{3}{5}x-\frac{1}{2}\)\(x=\frac{-7}{20}\)
tìm x
a,\(\frac{x-3}{x+5}\)= \(\frac{5}{7}\)
b,\(\frac{7}{x-1}\)= \(\frac{x+1}{9}\)
c, \(\frac{x-1}{x+2}\)= \(\frac{x-2}{x+3}\)
d, \(\frac{11x-2}{7x+5}\)= \(\frac{11}{8}\)
Tìm các cặp số x, y biết:
a) \(\frac{2x+1}{5}=\frac{4y-2}{7}=\frac{2x+4y-1}{6x}\)
b) \(\frac{1+3y}{12}=\frac{1+5y}{5x}=\frac{1+7y}{4x}\)
c) \(\frac{1+2x}{15}=\frac{7-3x}{20}=\frac{3y}{23+7x}\)
Tìm x, biết :
1) x+1 / x-2 = 3/4
2) 2x - 3 / x+1 = 4/7
3) 2x + 3 / 7 = 4x-1/15
4) 11x - 2 / 7x + 5 = 11/8
5) 12 - 7x / -13 = 4 - 3x / -5
Câu 1: Thực hiện phép tính bằng cách hợp lí
\(\frac{15}{35}+\frac{7}{21}+\frac{19}{34}-1\frac{15}{17}+\frac{2}{3}\)
\(\left(-2\right)^3.\left(\frac{3}{4}-0,25\right):\left(2\frac{1}{4}-1\frac{1}{6}\right)\)
\(16\frac{2}{7}:\left(-\frac{3}{5}\right)+28\frac{2}{7}:\left(-\frac{3}{5}\right)\)
Câu 2: Tìm x biết
\(2.x-\frac{5}{4}=\frac{20}{15}\)
\(1,5:0,3=x:-15\)
\(|2x-1|=2\)
Câu 3: Thực hiện phép tính hợp lí
\(\frac{11}{12}.\frac{15}{33}+\frac{11}{12}.\frac{2}{22}\)
\(3/3\frac{1}{8}.11\frac{17}{19}-3\frac{1}{8}.13\frac{17}{19}\)
\(28\frac{2}{7}:\left(-\frac{3}{5}\right)+16\frac{2}{7}:\left(-\frac{3}{5}\right)\)
Bài 1 : Tìm x biết :
a, \(\left|\frac{3}{2}x+\frac{1}{2}\right|=\left|4x-1\right|\)
b, \(\left|\frac{5}{4}x-\frac{7}{2}\right|-\left|\frac{5}{8}x+\frac{3}{5}\right|=0\)
c,\(\left|\frac{7}{5}x+\frac{2}{3}\right|=\left|\frac{4}{3}x-\frac{1}{4}\right|\)
Bài 2 : Tìm x biết :
a, | 2x - 5 | = x +1
b, | 3x - 2 | -1 = x
c, | 3x - 7 | = 2x + 1
d, | 2x-1 | +1 = x