Toán Lớp 8: a.2x-3^2-10x+15=0
b.4x+1.x-2-2x-3^2=4
Tìm x.
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 8: a.2x-3^2-10x+15=0
b.4x+1.x-2-2x-3^2=4
Tìm x.
Comments ( 1 )
a) 2x – 3^2 – 10x + 15 = 0
⇔ 2x – 9 – 10x + 15 = 0
⇔ ( 2x – 10x ) + ( 15 – 9 ) = 0
⇔ -8x + 6 = 0
⇔ -8x = -6
⇔ x = 6 / 8
⇔ x = 3/4
Vậy x = 3/4
____________________________
b) 4x + 1 . x – 2 – 2x – 3^2 = 4
⇔ 4x + x – 2x – 2 – 9 = 4
⇔ 3x – 11 = 4
⇔ 3x = 4 + 11
⇔ 3x = 15
⇔ x = 15 : 3
⇔ x = 5
Vậy x = 5