Ответы на вопрос:
4(10x−21)^2−17(10x−21)+4=0
10х - 21 = t
4t² - 17t + 4 = 0
d = 17² - 4*4*4 = 289 - 62 = 225
t12 = (17 +- 15)/8 = 4 1/4
1. t1 = 4
10x - 21 = 4
10x = 25
x = 25/10 = 5/2 = 2.5
2. t2 = 1/4
10x - 21 = 1/4
40x - 84 = 1
40x = 85
x = 85/40 = 17/8 = 2.125
Популярно: Алгебра
-
kurroro25.02.2021 21:26
-
aikos9830.12.2022 10:43
-
bcvfb23.06.2020 12:53
-
AnnaMax11127.06.2022 02:33
-
on8220.08.2022 14:48
-
IronManGold22.06.2022 19:03
-
Rafaelnodat115.02.2022 00:16
-
Stepanovayu240523.06.2023 22:57
-
Учен58622.03.2020 18:43
-
Дашанеси31.10.2020 23:46