Đáp án:
B1 a)7x-35=0⇔x=5
b)4x-x-18=0⇔3x=18⇔x=6
c)x-6=8-x⇔2x=14⇔x=7
d)48-5x=39-2x⇔3x=9⇔x=3
B2 a)5x-8=4x-5⇔x=3
b)4-(x-5)=5(x-3x)⇔9-x=-10x⇔9x=9⇔x=1
c)32-4(0,5y-5)=3y+2⇔32-2y+20=3y+2⇔5y=50⇔y=10
d)2,5(y-1)=2,5y⇔2,5y-2,5=2,5y⇔0=2,5⇒PT vô nghiệm
B3 a)3x-7/5=2x-1/3⇔9x-21=10x-5⇔x=-16
b)4x+7/12+x=3x/8⇔24x+42+48x=18x⇔54x=-42⇔x=-21/27
B4 a)5x-8/3=1-3x/2⇔10x-16=3-9x⇔19x=19⇔x=1
b)x-5/6-x-9/4=5x+3/8+2⇔4x-20-6x-54=15x+9+48⇔17x=-131⇔x=-131/17
B5 a)6(x-7)=5(x+2)+x⇔6x-42=5x+10+x⇔0=52⇒PT vô nghiệm
b)5x-8=2(x+4)+3⇔5x-8=2x+8+3⇔3x=19⇔x=19/3
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