(2.8-0.1х)*3.7=7.4
2.8-0.1х=7.4:3.7
2.8-0.1х=2
-0.1х=2-2.8
-0.1х=-0.8
х=-0.8:(-0.1)
х=8
у = -0,5х² - 14,01,
х₀ = -в / 2а,
х₀ = -(-14,01) / 2*(-0,5) = -14,01 / 1 = -14,01,
у₀ = -(в² - 4ас) / 4а,
у₀ = -(14,01² - 4*(-0,5)*0) / 4*(-0,5) = -196,2801 / (-2) = 98,14005,
(-14,01; 98,14005)
Х=4+2 х= 3+2
х=6 х=-2-3
х= -5
6-2х<3х-3
-2х-3х<-3-6
-5х<-9
5х>9
х>1,8
ответ: (1,8; бесконечности)