Question

Помогите Пожалуйста!!!​

Answer 1

Решение:

1

$\\\frac{7x-42}{4} =\frac{5x+5}{3} -3x-6\\\frac{7x-42}{4} = \frac{5x+5-9x-18}{3}\\\frac{7x-42}{4} = \frac{-4x-13}{3}\\-16x-52=21x-126\\21x+16x=126-52\\37x=74\\x = 2$

2

$\frac{3(x-8)}{5}+\frac{7(x+5)}{6} =\frac{4(7x+1.5)}{15}+\frac{1}{3} \\\frac{18(x-8)+35(x+5)}{30} =\frac{4(7x+1.5)+5}{15}\\\frac{18x-144+35x+175}{30} =\frac{28x+6+5}{15}\\\frac{53x+31}{30} =\frac{28x+11}{15}\\840x+330 = 795x+465\\840x - 795x = 465 - 330\\45x = 135\\x = 3$

3

$\frac{3(2x+5)}{8}-\frac{2(5x+7)}{3} =\frac{7(x-15)}{4}-6\frac{7}{8}\\\frac{3(2x+5)}{8}-\frac{2(5x+7)}{3} -\frac{7(x-15)}{4}=-\frac{55}{8}\\\frac{9(2x+5)-16(5x + 7)-42(x-15)}{24} =-\frac{55}{8}\\\frac{18x+45-80x-112-42x + 630}{24} = -\frac{55}{8}\\\frac{-104x+563}{24} = -\frac{55}{8}\\4504-832x = -1320\\-832x = -5824\\x = 7$