tím x
a) 12 . ( x - 4 ) + 3 . ( 2x + 5 ) = 16
b) -10 . ( 2x + 4 ) - 2 . ( 6 - 15x ) = 48
Những câu hỏi liên quan
tím x a) 12 . ( x - 4 ) + 3 . ( 2x + 5 ) = 16
b) -10 . ( 2x + 4 ) - 2 . ( 6 - 15x ) = 48
ai giup mik vs mik k cho
a) => (12x-4)+(6x+15)=16
=>12x-48+6x+15=16
=>(12x+6x)-(15-48)=16
=>18x-(-33)=16
=>18x=16+(-33)
=>18x=-17
=>x=-17/18
KL
b) =>(-20x+(-40))-(12-30x)=48
=>-20x+(-40)-12+30x=48
=>(-20x+30x)+(-40-12)=48
=>10x+(-52)=48
=>10x=48-(-52)
=>10x=4
=>x=4/10
KL
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a) 12( x - 4 ) + 3( 2x + 5 ) = 16
<=> 12x - 48 + 6x + 15 = 16
<=> 18x - 33 = 16
<=> 18x = 49
<=> x = 49/18
b) -10( 2x + 4 ) - 2( 6 - 15x ) = 48
<=> -20x - 40 - 12 + 30x = 48
<=> 10x - 52 = 48
<=> 10x = 100
<=> x = 10
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2. tìm x
a, \(3\sqrt{2x}\) + \(\sqrt{8x}\) - \(\sqrt{18x}\)= 16
b, \(\sqrt{4x+20}\) - \(3\sqrt{x+5}\) + \(\dfrac{4}{3}\) \(\sqrt{9x+45}\) = 6
\(a,3\sqrt{2x}+\sqrt{8x}-\sqrt{18x}=16\left(dk:x\ge0\right)\\ \Leftrightarrow3\sqrt{2x}+2\sqrt{2x}-3\sqrt{2x}=16\\ \Leftrightarrow\sqrt{2x}\left(3+2-3\right)=16\\ \Leftrightarrow2\sqrt{2x}=16\\ \Leftrightarrow\sqrt{2x}=8\\ \Leftrightarrow\left|2x\right|=64\\ \Leftrightarrow2x=64\\ \Leftrightarrow x=32\left(tm\right)\)
Vậy \(S=\left\{32\right\}\)
\(b,\sqrt{4x+20}-3\sqrt{x+5}+\dfrac{4}{3}\sqrt{9x+45}=6\left(dk:x\ge-5\right)\)
\(\Leftrightarrow\sqrt{4\left(x+5\right)}-3\sqrt{x+5}+\dfrac{4}{3}\sqrt{9\left(x+5\right)}=6\\ \Leftrightarrow2\sqrt{x+5}-3\sqrt{x+5}+4\sqrt{x+5}=6\\ \Leftrightarrow\sqrt{x+5}\left(2-3+4\right)=6\\ \Leftrightarrow3\sqrt{x+5}=6\\ \Leftrightarrow\sqrt{x+5}=2\\ \Leftrightarrow\left|x+5\right|=4\\ \Leftrightarrow x+5=4\\ \Leftrightarrow x=-1\left(tm\right)\)
Vậy \(S=\left\{-1\right\}\)
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tìm x
a) 4(18-5x)-12(3x-7)=15(2x-16)-6(x+14)
b) 5(3x+5)-4(2x-3)=5x+3(2x+12)+1
c) 2(5x-8)-3(4x-5)=4(3x-4)+11
a) \(\Rightarrow72-20x-36x+84=30x-240-6x-84\)
\(\Rightarrow80x=480\Rightarrow x=6\)
b) \(\Rightarrow15x+25-8x+12=5x+6x+36+1\)
\(\Rightarrow4x=0\Rightarrow x=0\)
c) \(\Rightarrow10x-16-12x+15=12x-16+11\)
\(\Rightarrow14x=4\Rightarrow x=\dfrac{2}{7}\)
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Tìm x, biết:1) 2x . (x-5) -x . (2x-4) 152) (x+1) . (x+2) - (x+4) . (x+3) 63) 4x2 - 4x+5 - x . (4x-3) 1-2x4) (x+3) . (2x+1) - 2x2 4x-55) -4 . (2x-8) + (2x-1) . (4x+3) 06) -3 . (x-2) + 4 . (2x-6) - 7 . (x-9) 5 . (3-2)7) (x-2) . (x+2) -2 . (x-4) 10. 3x8) 15x . (x-2) - (5x-1) . (3x + 1) 69) (2x+4) . (x-3) - x . (2x-10) 15-20x10) (4x-2) . (3x+4) - (2x-1) . (6x+5) 100 HEPL ME !!! Cần làm gấp những bài này, ai lm dc mk tick cho ng đó nha !!! THANK YOU !!!!
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Tìm x, biết:
1) 2x . (x-5) -x . (2x-4) = 15
2) (x+1) . (x+2) - (x+4) . (x+3) = 6
3) 4x2 - 4x+5 - x . (4x-3) = 1-2x
4) (x+3) . (2x+1) - 2x2 = 4x-5
5) -4 . (2x-8) + (2x-1) . (4x+3) = 0
6) -3 . (x-2) + 4 . (2x-6) - 7 . (x-9)= 5 . (3-2)
7) (x-2) . (x+2) -2 . (x-4) = 10. 3x
8) 15x . (x-2) - (5x-1) . (3x + 1) = 6
9) (2x+4) . (x-3) - x . (2x-10) =15-20x
10) (4x-2) . (3x+4) - (2x-1) . (6x+5) = 100
HEPL ME !!! Cần làm gấp những bài này, ai lm dc mk tick cho ng đó nha !!! THANK YOU !!!!
Tìm x, biết:
1) 2x ( x - 5) - x ( 2x - 4 ) = 15
<=> 2x2 - 10x - 2x2 + 4x - 15 = 0
<=> -6x - 15 = 0
<=> -6x = 15
<=> x = -15/6
2) ( x +1)( x + 2 ) - ( x + 4 ) ( x + 3 ) = 6
<=> x2 + 2x + x + 2 - x2 - 3x - 4x - 12 - 6 = 0
<=> -4x = -16
<=> x = 4
3) 4x2 - 4x + 5 - x ( 4x - 3) = 1 - 2x
<=> 4x2 - 4x + 5 - 4x2 + 3x - 1 + 2x = 0
<=> x + 4 = 0
<=> x = -4
4) ( x + 3 ) ( 2x + 1 ) - 2x2 = 4x - 5
<=> 2x2 + x + 6x + 3 - 2x2 - 4x + 5 = 0
<=> 3x + 8 = 0
<=> 3x = -8
<=> x = -8/3
5) -4 ( 2x - 8 ) + ( 2x - 1 )( 4x + 3 ) = 0
<=> - 8x + 32 + 8x2 + 6x - 4x - 3 = 0
.......
6) -3 . (x-2) + 4 . (2x-6) - 7 . (x-9)= 5 . (3-2)
<=> -3x + 6 + 8x - 24 - 7x + 63 - 5 = 0
<=> -2x + 40 = 0
<=> -2x = -40
<=> x = 20
Còn lại tương tự ....
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Xem thêm câu trả lời
Bài 1: Tìm x
a,(2x-3)2-10x2+15x=0
b,49.(x-5)2-4.(2x+1)=0
c,(x+6)2-8x-48=0
d,64.(2x+3)2-(x-6)2=0
a: \(\Leftrightarrow\left(2x-3\right)^2-5x\left(2x-3\right)=0\)
=>(2x-3)(-3x-3)=0
=>x=-1 hoặc x=3/2
b: \(\Leftrightarrow49\left(x^2-10x+25\right)-8x-4=0\)
=>\(49x^2-498x+1221=0\)
=>\(x\in\left\{6.03;4.13\right\}\)
c: \(\Leftrightarrow\left(x+6\right)\left(x+6-8\right)=0\)
=>(x-2)(x+6)=0
=>x=2 hoặc x=-6
d: =>\(\left(16x+24\right)^2-\left(x-6\right)^2=0\)
=>(16x+24+x-6)(16x+24-x+6)=0
=>(17x+18)(15x+30)=0
=>x=-2 hoặc x=-18/17
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phân tích đa thức thành nhân tử 1, A = 2x^2 + 5x^3 + x^2y 2, A = 4x^2y - 8xy^2 + 18x^2y^2 3, A = -3x^2y + 6x^2 y^2 4, A = 2x^3 y^4 - 4x^5 y^6 + 6y^7 x^8 5, A = 14x^2y - 21xy^2 + 28x^2 y^2 6, A = -8x^4 y^3 - 12x^2 y^4 + 20x^3 y^4 7, A = 5x . (x - 1) - 15x . (1 - x) 8, A = 2x^2 . (y - 1) - 15x . (1 - x) 9, A = 9x^2 . (y + z ) + 3x . (y + z) 10, A = 10x . ( x - y) - 8y . (y - x) 11, A = 2x . ( x + y) - 6x^2 . (x + y) 12, A = 10xy . ( x - y) - 6y . (y - x) giải giúp e với ạ
Xem chi tiết
a,x^2+2x/(x+1)^2+3-x^2-2x/(x-1)^2+3=16/x^4+4x^2+16
b,x^2/x^2+2x+2+x^2/x^2-2x+2=5(x^2-5)/x^4+4+25/4
1. 4 + x = 7 - 2x
2. 5 + x = 8,3 + 4,7 - x
3. x + 12 = 35 + ½x
4. 6 + x = 7⅓ + 2 - x
5. 20x + 4 = 19,2 + 15x
6. x + 5 = 8 2/5 - 4x
7. 3 (x +1) = 13,5
8. 32 - (32 - x) = 32
9. 5x - 12 3/5 = 0
10. x - 10/3 = 0
P/s : Please, help me 😋😋
4 + x = 7 - 2x
4 + x + 2x = 7
4 + 3x = 7
3x = 7 - 4
3x = 3
x = 3 : 3
x =1
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5 + x = 8,3 + 4,7 - x
5 + x + x = 8,3 + 4,7
5 + 2x = 13
2x = 13 - 5
2x = 8
x = 8 : 2
x= 4
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5(7+48:x)=45
5^2x-3-2*5^2=5^2*3
2+x:5=6
10+2x=4^5:4^3
\(5\left(7+48:x\right)=45\)
\(\Leftrightarrow\left(7+48x\right)=9\)
\(\Leftrightarrow4x=2\)
\(\Leftrightarrow x=2\)
________________
\(5^2x-3.2.5^2=5^2.3\)
\(\Leftrightarrow5x^2-3-2.5^2=75\)
\(\Leftrightarrow5x^2-3-50=75\)
\(\Leftrightarrow5x^2-3=125\)
\(\Leftrightarrow5x^2=128\)
\(\Leftrightarrow x^2=\frac{128}{5}\)
\(\Leftrightarrow\orbr{\begin{cases}x=\frac{128}{5}\\x=-\frac{128}{5}\end{cases}}\)
___________________
\(2+x:5=0\)
\(\Leftrightarrow x:5=-2\)
\(\Leftrightarrow x=-10\)
\(10+2x=16\)
\(\Leftrightarrow2x=6\)
\(\Leftrightarrow x=3\)
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