Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a) \(15-5\left|x+4\right|=-12-3\)
\(\Leftrightarrow5\left|x+4\right|=30\)
\(\Leftrightarrow\left|x+4\right|=6\)
\(\Leftrightarrow\orbr{\begin{cases}x+4=6\\x+4=-6\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=2\\x=-10\end{cases}}\)
b) \(\left(4x-8\right)\left(7-x\right)=0\Leftrightarrow\orbr{\begin{cases}4x-8=0\\7-x=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=2\\x=7\end{cases}}\)
c) \(\left(x^2-36\right)\left(x^2+5\right)=0\Rightarrow\left(x-6\right)\left(x+6\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}x-6=0\\x+6=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=6\\x=-6\end{cases}}\)
d) \(-3\left(x+7\right)-11=2\left(x+5\right)\)
\(\Leftrightarrow-3x-32=2x+10\)
\(\Leftrightarrow5x=-42\Rightarrow x=-\frac{42}{5}\)
\(a,\left(4x-8\right)\left(12-y\right)=0\)
\(\Rightarrow\hept{\begin{cases}4x-8=0\\12-y=0\end{cases}}\)
\(\Rightarrow\hept{\begin{cases}4x=8\\y=12\end{cases}}\)
\(\Rightarrow\hept{\begin{cases}x=2\\y=12\end{cases}}\)
\(b,\left(2x-12\right)-14=86\)
\(\Rightarrow2\left(x-6\right)=86+14=100\)
\(\Rightarrow x-6=50\)
\(\Rightarrow x=50+6=56\)
\(c,\left(127-x\right)-17=43\)
\(\Rightarrow127-x=43+17=60\)
\(\Rightarrow x=127-60=67\)
\(\left(4x-8\right)\left(12-y\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}4x-8=0\\12-y=0\end{cases}\Leftrightarrow\orbr{\begin{cases}4x=8\\y=12-0\end{cases}\Leftrightarrow}\orbr{\begin{cases}x=2\\y=12\end{cases}}}\)
Vậy x = 2 hoặc y = 12
\(\left(2x-12\right)-14=86\)
\(\Leftrightarrow2x-12=100\)
\(\Leftrightarrow2x=112\)
\(\Leftrightarrow x=56\)
Vậy x = 56
\(\left(127-x\right)-17=43\)
\(\Leftrightarrow127-x=60\)
\(\Leftrightarrow x=127-60\)
\(\Leftrightarrow x=67\)
Vậy x = 67
\(1)\)
\(-3-18\)
\(=-(3+18)\)
\(=-21\)
\(-7\times-5\)
\(=7\times(-1)\times(-5)\)
\(=7\times5\)
\(=35\)
\(5+(-11)\)
\(=5-11\)
\(=-6\)
1,
a) -3 - 18=-21
b) (-7).(-5)=35
c) 5+(-11)=-6
2,
a) -2-13+(-14)-19=-48
b) 221 + 4[(-5).8-4]=45
c) (-2)3.(-2)2+32=0
d) -15.12 - 8.(-12)=-84
3,
a) x:(-2)=9
=>x =9.(-2)
=>x =-18
b)4x+(-8)=24
=>4x =24-(-8)
=>4x =32
=>x =32:4
=>x =8
c) (3x)(x+7)=0
\(\Rightarrow\hept{\begin{cases}3x=0\\x+7=0\end{cases}\Rightarrow\hept{\begin{cases}x=0:3\\x=0-7\end{cases}\Rightarrow}\hept{\begin{cases}x=0\\x=-7\end{cases}}}\)
a)= ( 81 , 6 x 27 , 3 – 17 , 3 x 81 , 6 ) x 0
=0 ( vì 0 nhân với số nào cũng bằng 0)
b)= ( 13 , 75 – 0 , 48 x 5 ) x ( 42 , 75 : 3 + 2 , 9 ) x ( 9-9)
= ( 13 , 75 – 0 , 48 x 5 ) x ( 42 , 75 : 3 + 2 , 9 ) x 0
= 0 ( vì 0 nhân với số nào cũng bằng 0)
c)=( 792 , 81 x 0 , 25 + 792 , 81 x 0 , 75 ) x 0
=0 ( vì 0 nhân với số nào cũng bằng 0 )
a ) ( 81 , 6 x 27 , 3 – 17 , 3 x 81 , 6 ) x ( 32 x 11 - 3200 x 0 , 1 - 32 )
= ( 81 , 6 x 27 , 3 – 17 , 3 x 81 , 6 ) x ( 352 - 320 - 32 )
= ( 81 , 6 x 27 , 3 – 17 , 3 x 81 , 6 ) x 0
= 0.
b ) ( 13 , 75 – 0 , 48 x 5 ) x ( 42 , 75 : 3 + 2 , 9 ) x ( 1 , 8 x 5 – 0 , 9 x 10 )
= ( 13 , 75 – 0 , 48 x 5 ) x ( 42 , 75 : 3 + 2 , 9 ) x ( 9 - 9 )
= ( 13 , 75 – 0 , 48 x 5 ) x ( 42 , 75 : 3 + 2 , 9 ) x 0
= 0
c ) ( 792 , 81 x 0 , 25 + 792 , 81 x 0 , 75 ) x ( 11 x 9 – 900 x 0 , 1 – 9 )
= ( 792 , 81 x 0 , 25 + 792 , 81 x 0 , 75 ) x ( 99 - 90 - 9 )
= ( 792 , 81 x 0 , 25 + 792 , 81 x 0 , 75 ) x 0
= 0.
Hok tốt !
bạn trình bày ra nhé họ o mình
câu 2 : 3*(x+1)=13,5 mới đúng mình viết nhầm
\(a)y-6:2-\left(48-24x2:6-3\right)=0\)\(0\)
\(y-3-\left(48-48:6-3\right)=0\)
\(y-3-\left(48-8-3\right)=0\)
\(y-3-\left(40-3\right)=0\)
\(y-3-37=0\)
\(y-\left(3+37\right)=0\)
\(y-40=0\)
\(y=0+40\)
\(y=40\)
\(b)\left(7x13+8x13\right):\left(9\frac{2}{3}-y\right)=39\)
\(\left(91+104\right):\left(\frac{29}{3}-y\right)=39\)
\(195:\left(\frac{29}{3}-y\right)=39\)
\(\frac{29}{3}-y=195:39\)
\(\frac{29}{3}-y=5\)
\(y=\frac{29}{3}-5\)
\(y=\frac{14}{3}\)
a) x - 26 : 13 = 2017
x - 2 = 2017
x = 2017 + 2
x = 2019
b) \(\frac{2}{3}+\frac{1}{3}.\left(x+28\right)=18\)
\(\frac{1}{3}.\left(x+28\right)=18-\frac{2}{3}\)
\(\frac{1}{3}.\left(x+28\right)=\frac{54}{3}-\frac{2}{3}\)
\(\frac{1}{3}.\left(x+28\right)=\frac{52}{3}\)
\(x+28=\frac{52}{3}:\frac{1}{3}\)
\(x+28=52\)
\(x=52-28\)
\(x=24\)
c) \(\frac{7}{8}.\left(x-27\right)=\frac{9}{8}-0,125\)
\(\frac{7}{8}.\left(x-27\right)=1\)
\(x-27=1:\frac{7}{8}\)
\(x-27=\frac{8}{7}\)
\(x=\frac{8}{7}+27\)
\(x=\frac{8}{7}+\frac{189}{7}\)
\(x=\frac{197}{7}\)
a) 4x:17=0
4x=0x17
4x=0
x=0:4
x=0
b)7x-8=713
7x=213+8
7x=221
x=221:7
x=221/7
c)8(x-3)=0
8x - 8x3 = 0
8x -24=0
8x=0+24
8x=24
x=24:8
x=3