Question

решите пожалуйста
12а-(3b-5a)
12a+(3b-5a)
x²=2-x

Answer 1

12а -(3b - 5a) =12a - 3b+5a =17a - 3b
12a + (3b -5b)  =12a+3b-5a=7a+3b
x² =2 - x
x² +x -2 =0
D = 1 +8 =9
x1 =(-1 +3)/2=1
x2 = (-1 -3 )/2 = -2