Решить) 5m-3)(1+4)=42-(10m+1)(3-2m) - вопрос №894392453144210132 от anna199015 18.09.2022 18:11

Question

Алгебра: Решить) 5m-3)(1+4)=42-(10m+1)(3-2m)

anna199015 · Answer

(5m-3)(1+4)=42-(10m+1)(3-2m)
5( 5m - 3 ) = 42 - ( 30m - 20m^2 + 3 - 2m )
25m - 15 = 42 + 20m^2 - 28m - 3
20m^2 - 28m - 25m - 3 + 15 = 0
20m^2 - 53m + 12 = 0
D = 2809 - 960 = 1849 = 43^2
m1 = ( 53 + 43 ) : 40 = 96 : 40 = 2,4
m2 = ( 53 - 43 ) : 40 = 10 : 40 = 0,25