Question

1)4x/9-x/15=2/3
2)х+7/3=2х+3/5
УМОЛЯЮ ПОМОГИТЕ ДАМ 30 БАЛЛОВ!

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Answer 1

$\tt\displaystyle 1)\ \frac{4x}{9}-\frac{x}{15}=\frac{2}{3} \\\\\\\frac{4x*5-x*3}{45}=\frac{2*15}{45}\\\\\\\frac{20x-3x}{45}=\frac{30}{45}\ |\ *45\\\\20x-3x=30\\\\17x=30\\\\\\x=\frac{30}{17}\\\\\\\bold{x=1 \frac{13}{17} }$

$\tt\displaystyle 2)\ \frac{x+7}{3}=\frac{2x+3}{5}\ |\ *15\\\\5(x+7)=3(2x+3)\\\\5x+35=6x+9\\\\-x=-26\\\\\bold{x=26}$

или

$\tt\displaystyle x+\frac{7}{3}=2x+\frac{3}{5}\\\\\\-x= \frac{3}{5}-\frac{7}{3}\\\\\\-x=\frac{3*3-5*7}{15}\\\\\\-x=\frac{9-35}{15} \\\\\\-x=\frac{-26}{15} \\\\\\\bold{x=1\frac{11}{15}}$