giải hộ mình vs
Bài 1 tính nhanh
a} 165+17+135
b}27+39+13+21
c}165.2+165.97+13+165
Bài 2 tìm x, biết
a}3x+7x+x+33=99
b}4x+16:2=164
Giúp mình v
Bài10872917292872917 tìm x bt
5x-16=40+x
4x-10=15-x
-12+x=5x-2
7x-4=20+3x
5x-7=20+3x
x+15=7+6x
17-x=7-6x
3x+(-21)=12-8x
125:(3x-13)=25
541+(218-z)=735
3(2x+1)-19=14
175-5(x+3)=85
4x-40=|4|+12
x+15=20-4x
8x+|-3|=-4x+39
6(x-2)+(-2)=20-4x
5x-16=40+x
=> 5x-16-x = 40
=> 5x-x -16=40
4x-16=40
4x= 40+16
4x=56
x= 56:4
x=14
Vậy...
4x-10=15-x
=> 4x-10+x= 15
4x+x -10=15
5x= 15+10
5x= 25
x= 25:5
x=5
Vậy....
5x -16=40+x
=> 5x-x=40+16
=>4x=56
=>x=56:4
x=14
1. tính bằng cách hợp lý nhất:
a) 19/27+9/7+6/27+5/7+2/7
b) 2/7+27/48+7/16+45/63
c) 17/23+( 4/7-6/13)
2. tìm x:
6/11+x=1
giải nhanh hộ mình vs nhé đang cần gấp
Bài 1:
a) 19/27+9/7+6/27+5/7+2/7
= (19/27+6/27) + (9/7+5/7+2/7)
=1 + 16/7
=23/7
b) 2/7 + 27/48 + 7/16 +45/63
= (2/7 + 45/63) + (27/48 +7/16)
= (2/7 + 5/7) + ( 9/16 + 7/16)
= 1 + 1
=2
c) Tính bằng cách bình thường
Bài 2:
6/11 + x = 1
x = 1-6/11
x = 5/11
Bài làm
a) \(\frac{19}{27}+\frac{9}{7}+\frac{6}{27}+\frac{5}{7}+\frac{2}{7}\)
\(=\frac{27}{27}+\frac{16}{7}\)
\(=1+\frac{16}{7}\)
\(=\frac{7}{7}+\frac{16}{7}\)
\(=\frac{23}{7}\)
b) \(\frac{2}{7}+\frac{27}{48}+\frac{7}{16}+\frac{45}{63}\)
\(=\left(\frac{18}{63}+\frac{45}{63}\right)+\left(\frac{27}{48}+\frac{21}{48}\right)\)
\(=\frac{63}{63}+\frac{48}{48}\)
\(=1+1\)
\(=2\)
c) \(\frac{17}{23}+\left(\frac{4}{7}-\frac{6}{13}\right)\)
\(=\frac{17}{23}+\left(\frac{52}{91}-\frac{42}{91}\right)\)
\(=\frac{17}{23}+\frac{10}{91}\)
\(=\frac{1547}{2093}+\frac{230}{2093}\)
\(=\frac{1770}{2093}\)
Bài 2
\(\frac{6}{11}+x=1\)
\(x=1-\frac{6}{11}\)
\(x=\frac{11}{11}-\frac{6}{11}=\frac{5}{11}\)
Vậy \(x=\frac{5}{11}\)
Cảm ơn 2 bn nhé
Giúp vs
Bài 1. Tìm x biết
a) (x+3)3=640000
b) 275.3x=910
c) (1/33.9).3x=27
d) 85.4x=221
Bài 2. Tính
M=22010-(22009+22008+...+21+20)
giải pt
x^2+4x-3|x+2|+4=0
4x^2+1/x^2+|2x-1/x|-6=0
2x/(3x^2-5x+2)+13x/(3x2+x+2)=6
2(x+1)/3x^2+x+13(x+1)/3x^2+7x+16=6
1: =>(x+2)^2-3|x+2|=0
=>|x+2|(|x+2|-3)=0
=>x+2=0 hoặc x+2=3 hoặc x+2=-3
=>x=-2; x=1; x=-5
1.(x+1)/35 + (x+3)/33 = (x+5)/33 + (x+7)/20
2. (X+1)/12+ (X+2)/13 = (X+3)/14+ (X+4)/15
3. (X-85)/15+ (X-75)/13+(X-67)/11+ (X-64)/9=10
4. (X-1)/13-(2X-13)/15=(3X-15)/27- (4X-27)/29
2: \(\Leftrightarrow\left(\dfrac{x+1}{12}-1\right)+\left(\dfrac{x+2}{13}-1\right)=\left(\dfrac{x+3}{14}-1\right)+\left(\dfrac{x+4}{15}-1\right)\)
=>x-11=0
=>x=11
3: \(\Leftrightarrow\left(\dfrac{x-85}{15}-1\right)+\left(\dfrac{x-74}{13}-2\right)+\left(\dfrac{x-67}{11}-3\right)+\left(\dfrac{x-64}{9}-4\right)=0\)
=>x-100=0
=>x=100
GIẢI PHƯƠNG TRÌNH
1)\(\dfrac{x+1}{35}+\dfrac{x+3}{33}=\dfrac{x+5}{31}+\dfrac{x+7}{29}\)
2)x(x+1)(x+2)(x+3)=24
3)\(\dfrac{x-1}{13}-\dfrac{2x-13}{15}=\dfrac{3x-15}{27}-\dfrac{4x-27}{29}\)
4)\(\dfrac{1909-x}{91}+\dfrac{1907-x}{93}+\dfrac{1905-x}{95}+\dfrac{1903-x}{91}+4=0\)
1) PT \(\Leftrightarrow\left(\dfrac{x+1}{35}+1\right)+\left(\dfrac{x+3}{33}+1\right)=\left(\dfrac{x+5}{31}+1\right)+\left(\dfrac{x+7}{29}+1\right)\)
\(\Leftrightarrow\dfrac{x+36}{35}+\dfrac{x+36}{33}=\dfrac{x+36}{31}+\dfrac{x+36}{29}\)
\(\Leftrightarrow\left(x+36\right)\left(\dfrac{1}{29}+\dfrac{1}{31}-\dfrac{1}{33}-\dfrac{1}{35}\right)=0\)
\(\Leftrightarrow x+36=0\) (Do \(\dfrac{1}{29}+\dfrac{1}{31}-\dfrac{1}{33}-\dfrac{1}{35}>0\))
\(\Leftrightarrow x=-36\).
Vậy nghiệm của pt là x = -36.
2) x(x+1)(x+2)(x+3)= 24
⇔ x.(x+3) . (x+2).(x+1) = 24
⇔(\(x^2\) + 3x) . (\(x^2\) + 3x + 2) = 24
Đặt \(x^2\)+ 3x = b
⇒ b . (b+2)= 24
Hay: \(b^2\) +2b = 24
⇔\(b^2\) + 2b + 1 = 25
⇔\(\left(b+1\right)^2\)= 25
+ Xét b+1 = 5 ⇒ b=4 ⇒ \(x^2\)+ 3x = 4 ⇒ \(x^2\)+4x-x-4=0 ⇒x(x+4)-(x+4)=0
⇒(x-1)(x+4)=0⇒x=1 và x=-4
+ Xét b+1 = -5 ⇒ b=-6 ⇒ \(x^2\)+3x=-6 ⇒\(x^2\) + 3x + 6=0
⇒\(x^2\) + 2.x.\(\dfrac{3}{2}\) + (\(\dfrac{3}{2}\))2 = - \(\dfrac{15}{4}\) Hay ( \(x^2\) +\(\dfrac{3}{2}\) )2= -\(\dfrac{15}{4}\) (vô lí)
⇒x= 1 và x= 4
tìm x biết
a, -5 (x^2 - 3x + 1 ) + x ( 1 +5x) = x-2
b,-4x ( x - 5 ) + 7x (x - 4 ) - 3x^ 2 = 12
Lời giải:
a.
PT $\Leftrightarrow -5x^2+15x-5+x+5x^2=x-2$
$\Leftrightarrow 16x-5=x-2$
$\Leftrightarrow 15x=3$
$\Leftrightarrow x=\frac{3}{15}=\frac{1}{5}$
b.
PT $\Leftrightarrow -4x^2+20x+7x^2-28x-3x^2=12$
$\Leftrightarrow -8x=12$
$\Leftrightarrow x=\frac{-3}{2}$
Tìm x, biết :
a, 2x - (-3x - 17) = 53 - 26 - x
b,5x - (-24) =33-78+4x
c,(7x - 19) - (5x -12) = 3x - (9-2x) -1
d,(2x +5)2 = -125
e,(4x - 3)2 = 289
f,-2*(12-5x)3 = -686
g,2mũ x+5 -3*2mũ x = 928
h,3mũ x +3 mũ x+1 + 3mũ x+2 = 13
Thực hiện phép tính (tính hợp lí nếu có thể)
a) 34 – 245 – 234 - 55
b) 113.39 - 39 -12.39
c) -200 -100 : [13 - 2.(17 - 4.5)2] .12021
Tìm số nguyên x , biết
a) ( x + 3) - 7 = 10
b) 2.(5 - x) = 22 - 23
c) 2x +1 là bội của x - 3