pliss dengan cara pake rumus abc

rumus abc = -b +- {b2- 4ac} / 2a

a. a = 2 , b = -1, c = 7
-(-1) +- {(1 - 56)} / 4
x1 = 1 + {55}/4
x2 = 1- {55}/4 =

b. a = 3 , b = 2, c = -4
-2 +- (4 - 4.3.-4} / 6
x1 = -2 + 2{13} / 6 = -1 + {13} / 3
x2 = -2 - 2{13} / 6 = -1 + {13} / 3

catatan : {} = akar
maaf kalau salah