2х +(5-7х) = 152х + 5 - 7х = 15-5х + 5 = 15-5х = 15 - 5-5х=10х= 10 : (-5)х = - 2===================2 *(-2) + (5 - 7 *(-2) ) = 15- 4 + (5 +14) = 15- 4 + 19 = 1515 = 155х + 3 =-3х + 195х +3х = 19 - 38х = 16х= 16:8х= 2================5*2 +3 = -3 * 2 +1910 + 3 = -6 + 1913 = 133х + 4(5-3х) = -73х + 4*5 + 4*(-3х) = -73х + 20 - 12х = -7-9х + 20 = -7-9х = -7 - 20-9х = -27х= -27 :(-9)х= 3================3*3 +4*(5 - 3*3) = -79 + 4* (5 - 9) = - 79 + 4 * (-4) = -79 - 16 = -7-7 = -7¹/₃ х +1 = ¹/₂ (х - ¹/₆)¹/₃ х + 1 = ¹/₂ х - ¹/₂ * ¹/₆¹/₃ х + 1 = ¹/₂ х - ¹/₁₂¹/₃ х - ¹/₂ х = - ¹/₁₂ - 1(¹/₃ - ¹/₂) * х = - 1 ¹/₁₂(²/₆ - ³/₆) х = - 1 ¹/₁₂ - ¹/₆ х = - ¹³/₁₂х= - ¹³/₁₂ : (-¹/₆) = - ¹³/₁₂ * (-⁶/₁) = ¹³/₂х = 6 ¹/₂==========================¹/₃ * 6 ¹/₂ + 1 = ¹/₂ *(6 ¹/₂ - ¹/₆)¹/₃ * ¹³/₂ + 1 = ¹/₂ * (6 ³/₆ - ¹/₆)¹³/₆ + 1 = ¹/₂ * 6 ¹/₃2 ¹/₆ + 1 = ¹/₂ * ¹⁹/₃3 ¹/₆ = ¹⁹/₆3 ¹/₆ = 3 ¹/₆