giải phương trình: x+7=9 b,(x+3) ²=9(x+3) c,2x-1=0 d,7x-1/6+2x=6-x/5 e,10x+3/5=1+6+8x/9 16/11/2021 Bởi Abigail giải phương trình: x+7=9 b,(x+3) ²=9(x+3) c,2x-1=0 d,7x-1/6+2x=6-x/5 e,10x+3/5=1+6+8x/9
a) x+7=9 x = 2 b) (x+3) ²=9(x+3) (x+3) ²-9(x+3)=0 (x+3).(x+3-9)=0 (x+3).(x-6)=0 ⇒ x+3=0 hoặc x-6=0 x =-3 x=6 c) 2x-1=0 2x=1 x=1/2 d) 7x-1/6+2x=6-x/5 9x-1/6=6-x/5 9x+x/5=6+1/6 9x+x/5=37/6 46x/5=37/6 46x.6=37.5 276x=185 x=185/276 e) 10x+3/5=1+6+8x/9 10x-8x/9=7-3/5 82x/9=32/5 82x.5=32.9 410x=288 x =144/205 xin hay nhất ạ Bình luận
a) x+7=9 =>x=9-7=2 b) (x+3)²=9(x+3) =>x+3=9 (chia cả 2 vế cho x+3) =>x=9-3 =>x=6 c) 2x-1=0 =>2x=1 =>x=1/2 d) 7x-1/6+2x=6-x/5 =>9x+x/5=6+1/6 =>46x/5=37/6 =>46x=37*5/6=185/6 =>x=185/276 e) 10x+3/5=1+6+8x/9 =>10x-8x/9=7-3/5 =>82x/9=32/5 =>82x=288/5 =>x=288/410=144/205 Bình luận
a) x+7=9
x = 2
b) (x+3) ²=9(x+3)
(x+3) ²-9(x+3)=0
(x+3).(x+3-9)=0
(x+3).(x-6)=0
⇒ x+3=0 hoặc x-6=0
x =-3 x=6
c) 2x-1=0
2x=1
x=1/2
d) 7x-1/6+2x=6-x/5
9x-1/6=6-x/5
9x+x/5=6+1/6
9x+x/5=37/6
46x/5=37/6
46x.6=37.5
276x=185
x=185/276
e) 10x+3/5=1+6+8x/9
10x-8x/9=7-3/5
82x/9=32/5
82x.5=32.9
410x=288
x =144/205
xin hay nhất ạ
a) x+7=9
=>x=9-7=2
b) (x+3)²=9(x+3)
=>x+3=9 (chia cả 2 vế cho x+3)
=>x=9-3
=>x=6
c) 2x-1=0
=>2x=1
=>x=1/2
d) 7x-1/6+2x=6-x/5
=>9x+x/5=6+1/6
=>46x/5=37/6
=>46x=37*5/6=185/6
=>x=185/276
e) 10x+3/5=1+6+8x/9
=>10x-8x/9=7-3/5
=>82x/9=32/5
=>82x=288/5
=>x=288/410=144/205