\(\dfrac{3}{2}x-\dfrac{7}{3}=-\dfrac{1}{4}\)
\(\dfrac{3}{2}x=-\dfrac{1}{4}+\dfrac{7}{3}=\dfrac{25}{12}\)
\(x=\dfrac{25}{12}:\dfrac{3}{2}=\dfrac{25}{18}\)
Chung minh:
a/ \(5^5-5^4+5^3⋮7\)
b/ \(7^6+7^5-7^4⋮11\)
c/ \(3^{x+2}-2^{x+3}+3^x-2^{x+1}⋮10\)
d/ \(3^{x+3}+3^{x+1}+2^{x+3}+2^{x+2}⋮6\)
Tìm x:
1) -3.(1-2x) - 4.(1+3x) = -5x + 5
2) 3.(2x - 5) - 6.(1 - 4x) = -3x + 7
3) (1 - 3x) - 2.(3x - 6) = -4x - 5
4) x.(4x - 3) - 2x.(2x - 1) = 5x - 7
5) 3x.(2x - 1) - 6x.(x + 2) = -3x + 4
6) (1 - 2x).3 - 4.(6x - 1) = 7x - 5
7) 6x - 3.(1 - 4x) - 5.(x + 1) = 2x + 7
8) 6.(1 - 3x) - 3.(2x + 5) = -10x + 7
9) 3x.(1 - 2x) + 6x^2 - 7x = 8.(1 - 2x) - 9
10) 2x.(1 + 3x) - 3x.(4 + 2x) = 3x - 4
Tìm x, biết
a, \(\dfrac{3}{7}+\dfrac{4}{7}x=\dfrac{1}{3}\)
b, \(25-\left(5-x\right)=-7\)
c, \(\dfrac{3}{4}+\dfrac{1}{4}:x=\dfrac{2}{5}\)
d, \(2x\left(x-\dfrac{1}{7}\right)=0\)
e, \(\left|\dfrac{1}{2}x-\dfrac{3}{4}\right|-7=-3\)
Tìm x:
\(\dfrac{7}{5}\)x-\(\dfrac{2}{3}\)=\(-\dfrac{4}{3}\)x-\(\dfrac{1}{4}\)
Bài 1: Tìm hai số x và y biết x : 2 = y : (-5) và x - y = -7
Bài 2: Tìm x, biết:
a) ( \(-\dfrac{1}{3}\))\(^3\) . x = \(\dfrac{1}{81}\)
Bài 3: Tính
a) (\(-\dfrac{1}{3}\))\(^7\) . 3\(^7\)
b) (0,125)\(^3\) . 512
c) \(\dfrac{90^2}{15^2}\)
d) \(\dfrac{790^4}{79^4}\)
tìm x biết
1) \(\dfrac{2}{3}+\dfrac{1}{3}:x=\dfrac{3}{5}\)
2) \(\left(\dfrac{2x}{3}-3\right):\left(-10\right)=\dfrac{2}{5}\)
3) \(2\dfrac{2}{3}:x=2\dfrac{1}{12}:\left(-0,06\right)\)
4) \(\dfrac{3}{7}+\dfrac{1}{7}:x=\dfrac{3}{14}\)
5) \(-\dfrac{3}{5}.x-\dfrac{1}{2}=-\dfrac{1}{7}\)
6) \(\dfrac{1}{5}+2x=-2\dfrac{1}{4}\)
7)\(-\dfrac{1}{2}:x=\dfrac{3}{8}:\dfrac{9}{16}\)
8)\(\dfrac{2}{3}:x=2\dfrac{1}{2}:\left(-0,3\right)\)
9) \(\dfrac{x}{3}=\dfrac{-2}{1,5}\)
1. tính
a) 3/7 + ( -5/2) + (-3/5)
b) -8/18 - 15/27
c) 4/5 - (-2/7) - 7/10
2. tìm x
a) x+1/4=4/3
b) -x - 2/3 = -6/7
c) x2 = 16
d) 2/3 + 5/3 x = 5/7
3. Cho ∆ ABC vuông tại A, có AB = AC gọi K là trung điểm của cạnh BC
a) CM: ∆AKB= ∆AKC
b) CM: AK vuông góc BC
a,2^12.3^54^6.81/(2^2.3)^6+8^4.3^5
b, 4.(-1/2)^3-2.(-1/2)^2+3.(-1/2)+1
c, 5x-7=3x+9
d, 5x-|9-7x|=3
e, -5+|3x-1|+6=|-4|
g, (x-1)^2=(x-1)^4
h, 5^-1.25=125
i, |x+1|+|x+2|+|x+3|=4x
Tìm X
(\(\dfrac{2}{5}+\dfrac{1}{4}\))(\(\dfrac{-x}{3}+\dfrac{1}{2}\))+\(\dfrac{2}{3}=\dfrac{7}{4}\)
\(\left(\dfrac{3}{5}-\dfrac{X}{2}\right)\left(\dfrac{4}{5}+\dfrac{1}{2}\right)-\dfrac{4}{3}=\dfrac{3}{2}\)
