Question

[Đinh Trâm Anh]

Answer 1

[HT.Phong (9A5)]

\(1)5\left(x-7\right)=0\\ x-7=0\\ x=7\\ 2)25\left(x-4\right)=0\\ x-4=0\\ x=4\\ 3)34\left(2x-6\right)=0\\ 2x-6=0\\ 2x=6\\ x=\dfrac{6}{2}\\ x=3\\ 4)2007\left(3x-12\right)=0\\ 3x-12=0\\ 3x=12\\ x=\dfrac{12}{3}\\ x=4\\ 5)47\left(5x-15\right)=0\\5x=15\\ x=\dfrac{15}{5}\\ x=3\\ 6)13\left(4x-24\right)=0\\ 4x-24=0\\ 4x=24\\ x=\dfrac{24}{4}\\ x=6\\ 7)49\left(6x-12\right)=0\\ 6x-12=0\\ 6x=12\\ x=\dfrac{12}{6}\\ x=2\)

Answer 2

[HT.Phong (9A5)]

\(8)17\left(5x-45\right)=0\\ 5x-45=0\\ 5x=45\\ x=\dfrac{45}{5}\\ x=9\\ 9)105\left(17x-34\right)=0\\ 17x-34=0\\ 17x=34\\ x=\dfrac{34}{17}\\ x=2\\ 10)57\left(9x-27\right)=0\\ 9x-27=0\\ 9x=27\\ x=\dfrac{27}{9}\\ x=3\\ 11)25+\left(15-x\right)=30\\ 15-x=30-25\\ 15-x=5\\ x=15-5\\ x=10\\ 12)43-\left(24-x\right)=20\\ 24-x=43-20\\ 24-x=23\\ x=24-23\\ x=1\\ 13)2\left(x-5\right)-17=25\\ 2\left(x-5\right)=17+25\\ 2\left(x-5\right)=42\\ x-5=\dfrac{42}{2}=21\\ x=21+5\\ x=26\\ 14)3\left(x+7\right)-15=27\\ 3\left(x+7\right)=27+15\\ 3\left(x+7\right)=42\\ x+7=\dfrac{42}{3}\\ x+7=14\\ x=14-7\\ x=7\)