1) 20*(х-4)=189-109 2) 2 *( 2х-15)+ 3 (3х-12) , х= 12 3) 2 *(х+ 11) (х +4)-3(2х+ 5), х=4 4)НОД (х;35)=5 НОД (х;24)=6

1) 20 * (х - 4) = 189 - 109;20х - 80 = 80;20х = 160;х = 8.Ответ: 8.2) 2 * ( 2х - 15) + 3(3х - 12) = 4х - 30 + 9х - 36 = 13х - 66 = 13 * 12 - 66 = 156 - 66 = 90 , х= 12;3) 2 * (х + 11) (х + 4) - 3(2х + 5) = (2х + 22)(х + 4) - 6х - 15 = 2х^2 + 8х + 22х + 88 - 6х - 15 = 2х^2 + 24х + 73 = 2 * 4^2 + 24 * 4 + 73 = 32 + 96 + 73 = 201, х=4;4) НОД (х;35) = 5,х = 5;НОД (х;24) = 6.х = 6.