Х² + 4х -45 -х -5 +14 = 0
х² +3х -36 = 0
D= b² - 4ac = 9 -4*(-36) = 9 + 144 = 153
х = (-3 +-√153)/2
3x+1)²=3x+1
(3x+1)²-(3x+1)=0
(3x+1)(3x+1-1)=0
3x+1=0 3x=0
3x=-1 x=0
x=-1/3
<span>Ответ: х=0, х=-1/3</span>
(√7+11)²=7+22√7+121=128+22√7
7,2<a<8.4 2)7.2<a<8.4
1/2.5<1/b<1/2 2/5<1/b<1/2
3) 7.2*2/5<a/b<8.4*1/2
144/50<a/b<4.2
2.88<a/b<4.2