Toán Lớp 6: 3x +20=-7
(2x -1).5=-15
giúp mik nha
Leave a reply
Register Now
Login
Lost Password
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Toán Lớp 6: 3x +20=-7
(2x -1).5=-15
giúp mik nha
Comments ( 2 )
$3x\:+20=-7$
$⇒3x+20-20=-7-20$
$⇒3x=-27$
$⇒x=-9$
Vậy $x=-9$
____________________________________
$\left(2x\:-1\right)\cdot 5=-15$
$⇒5\left(2x−1\right)=−15$
$⇒2x-1=-\dfrac{15}{5}$
$⇒2x-1=-3$
$⇒2x-1+1=-3+1$
$⇒2x=-2$
$⇒x=-1$
Vậy $x=-1$
Giải đáp+giải thích các bước giải:
3x + 20 = -7
3x = -7 -20
3x = -27
x =-27 : 3
x = -9
(2x – 1). 5 =-15
(2x – 1) = -15 : 3
2x – 1 = -5
2x = -5+1
2x = 4
x = 4:2
x = 2