tìm x
3.8x - 2.23.x-16=0
92x-1=\(\dfrac{1}{3}\)
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bài 3 tìm x
a)(2x+3)^2-(2x+1)(2x-1)=32
b)(4x+3)(4x-3)-(4x-5)^2=46
c)(x+4)^2+(x+3)(x-3)-5(x+1)(x-1)=16
d)92x-1)^2+(x+3^2-5(x+7)(x-7)=0
e)25x^2-9=0
2(X-1)(X+1)-92X^2-3)=0
Tìm x:
a) \(\dfrac{1}{3}.x+\dfrac{2}{5}\left(x-1\right)=0\)
b)\(-5.\left(x+\dfrac{1}{5}\right)-\dfrac{1}{2}.\left(x-\dfrac{2}{3}\right)=x\)
c)\(\left(x+\dfrac{1}{2}\right).\left(\dfrac{2}{3}-2x\right)=0\)
d)\(9.\left(3x+1\right)^2=16\)
a: =>1/3x+2/5x-2/5=0
=>11/15x-2/5=0
=>11/15x=2/5
=>x=2/5:11/15=2/5*15/11=30/55=6/11
b: =>-5x-1-1/2x+1/3=x
=>-11/2x-2/3-x=0
=>-13/2x=2/3
=>x=-2/3:13/2=-2/3*2/13=-4/39
c: (x+1/2)(2/3-2x)=0
=>x+1/2=0 hoặc 2/3-2x=0
=>x=1/3 hoặc x=-1/2
d: 9(3x+1)^2=16
=>(3x+1)^2=16/9
=>3x+1=4/3 hoặc 3x+1=-4/3
=>3x=1/3 hoặc 3x=-7/3
=>x=1/9 hoặc x=-7/9
Tìm x biết:
1-(\(5\dfrac{3}{8}\)+x\(-7\dfrac{5}{24}\)):(\(-16\dfrac{2}{3}\))=0
`1-(5 3/8+x-7 5/24):(-16 2/3)=0`
`=>1-(5+3/8+x-7-5/24):(-50/3)=0`
`=>1=(x-2-11/6):(-50/3)`
`=>1=(x-11/6):(-50/3)`
`=>x-11/6=-50/3`
`=>x=-89/6`
Vậy `x=-89/6`
\(1-\left(5\dfrac{3}{8}+x-7\dfrac{5}{24}\right):\left(-16\dfrac{2}{3}\right)=0\)
\(\Leftrightarrow1-\left(\dfrac{43}{8}+x-\dfrac{173}{24}\right):\dfrac{50}{3}=0\)
\(\Leftrightarrow1-\left(\dfrac{129}{24}-\dfrac{173}{24}+x\right).\dfrac{3}{50}=0\)
\(\Leftrightarrow1+\dfrac{11}{6}-x.\dfrac{3}{50}=0\)
\(\Leftrightarrow\dfrac{17}{6}-x.\dfrac{3}{50}=0\)
\(\Leftrightarrow x.\dfrac{3}{50}=\dfrac{17}{6}\)
\(\Leftrightarrow x=\dfrac{425}{9}\)
-Chúc bạn học tốt-
\(1-\left(5\dfrac{3}{8}+x-7\dfrac{5}{24}\right):\left(-16\dfrac{2}{3}\right)=0\)
\(1-\left(\dfrac{43}{8}:\dfrac{-50}{3}+x:\dfrac{-50}{3}-\dfrac{173}{24}:\dfrac{-50}{3}\right)=0\)
\(1-\dfrac{-129}{400}-x:\dfrac{-50}{3}+\dfrac{-173}{400}=0\)
\(\left(1+\dfrac{129}{400}+\dfrac{-173}{400}\right)-x:\dfrac{-50}{3}=0\)
\(\dfrac{89}{100}-x:\dfrac{-50}{3}=0\)
\(x:\dfrac{-50}{3}=\dfrac{89}{100}-0\)
\(x:\dfrac{-50}{3}=\dfrac{89}{100}\)
\(x=\dfrac{89}{100}.\dfrac{-50}{3}\)
\(x=\dfrac{-89}{6}\)
Tìm x, biết:
a, \(\left(2\dfrac{3}{4}-1\dfrac{4}{5}\right)x=1\)
b, \(x^2-9\) \(3-5x=0\)
c, \(\left|3x-1\right|+2\dfrac{3}{4}=3\dfrac{1}{16}\)
a) \(\left(2\dfrac{3}{4}-1\dfrac{4}{5}\right)\cdot x=1\)
\(\left(\dfrac{11}{4}-\dfrac{9}{5}\right)\cdot x=1\)
\(\dfrac{19}{20}x=1\)
\(x=\dfrac{20}{19}\)
Vậy \(x=\dfrac{20}{19}\)
b) \(\left(x^2-9\right)\left(3-5x\right)=0\)
TH1:
\(x^2-9=0\)
\(x^2=9\)
\(x^2=3^2=\left(-3\right)^2\)
=>\(x\in\left\{3;-3\right\}\)
TH2:
\(3-5x=0\)
\(5x=3\)
\(x=\dfrac{3}{5}\)
Vậy \(x\in\left\{3;-3;\dfrac{3}{5}\right\}\)
10x+3/12=1+6:8x/9
2x+7x5 5x+1=0
2x(x-5)-x+5=0
(x+3)^2-(5-x)(x+3)=0
(x+2)(3-4x)=x^2+4x+4
bạn viết rõ đề câu a;b nhé
c, \(2x\left(x-5\right)-\left(x-5\right)=0\Leftrightarrow\left(2x-1\right)\left(x-5\right)=0\Leftrightarrow x=\dfrac{1}{2};x=5\)
d, \(\left(x+3\right)\left(x+3-5+x\right)=0\Leftrightarrow\left(x+3\right)\left(2x-2\right)=0\Leftrightarrow x=-3;x=1\)
e, \(\left(x+2\right)\left(3-4x\right)=\left(x+2\right)^2\Leftrightarrow\left(x+2\right)\left(3-4x-x-2\right)=0\)
\(\Leftrightarrow\left(x+2\right)\left(-5x+1\right)=0\Leftrightarrow x=-2;x=\dfrac{1}{5}\)
Cho biểu thức A = \(\dfrac{x+4}{\sqrt{x}+4}\) ; B = \(\left(\dfrac{x+3\sqrt{x}-3}{x-16}-\dfrac{1}{\sqrt{x}+4}\right):\dfrac{\sqrt{x}+1}{\sqrt{x}-4}\)
x ≥ 0, x ≠ 16
a) Rút gọn
b) Tìm giá trị nhỏ nhất của biểu thức \(\dfrac{A}{B}\)
(mink đag cần gấp)
a) Ta có: \(B=\left(\dfrac{x+3\sqrt{x}-3}{x-16}-\dfrac{1}{\sqrt{x}+4}\right):\dfrac{\sqrt{x}+1}{\sqrt{x}-4}\)
\(=\left(\dfrac{x+3\sqrt{x}-3-\sqrt{x}+4}{\left(\sqrt{x}+4\right)\left(\sqrt{x}-4\right)}\right):\dfrac{\sqrt{x}+1}{\sqrt{x}-4}\)
\(=\dfrac{x+2\sqrt{x}+1}{\left(\sqrt{x}+4\right)\left(\sqrt{x}-4\right)}\cdot\dfrac{\sqrt{x}-4}{\sqrt{x}+1}\)
\(=\dfrac{\sqrt{x}+1}{\sqrt{x}+4}\)
Giải các phương trình sau:
a) x − 2 2 − 2 x + 3 2 = 0 ;
b) 9 2 x + 1 2 − 4 x + 1 2 = 0 ;
c) x + 1 2 + 2 x + 1 + 1 = 0 ;
d) x − 1 x 2 − 9 + x + 3 = 0 .
A ) tìm x < 0 biết \(\dfrac{x}{4}\) = \(\dfrac{16}{x}\)
B ) tính tỉ số của 2 ngày và 3\(\dfrac{1}{5}\) giờ
C ) \(\dfrac{2}{3}\) số -5\(\dfrac{1}{7}\) là bao nhiêu
b: Tỉ số giữa 48 giờ và 3,2 giờ là:
48:3,2=15:1
c: \(\dfrac{-36}{7}\cdot\dfrac{2}{3}=\dfrac{-72}{21}=\dfrac{-24}{7}\)
Tìm x biết:
\(a,\left(x-\dfrac{3}{4}\right)+50\%=\dfrac{1}{6}\)
\(b,\dfrac{1}{2}x-\dfrac{5}{6}x=\dfrac{7}{2}\)
\(c,\left(4-x\right)\left(3x+5\right)=0\)
\(d,\dfrac{x}{16}=\dfrac{50}{32}\)
\(e,\left(2x-3\right)+\dfrac{3}{2}=-\dfrac{1}{4}\)
a: =>x-3/4=1/6-1/2=1/6-3/6=-2/6=-1/3
=>x=-1/3+3/4=-4/12+9/12=5/12
b: =>x(1/2-5/6)=7/2
=>-1/3x=7/2
hay x=-21/2
c: (4-x)(3x+5)=0
=>4-x=0 hoặc 3x+5=0
=>x=4 hoặc x=-5/3
d: x/16=50/32
=>x/16=25/16
hay x=25
e: =>2x-3=-1/4-3/2=-1/4-6/4=-7/4
=>2x=-7/4+3=5/4
hay x=5/8