Question

27.Calculați a) 5 × ( a+b) stiind ca a+b =-100
b) a × (b +c) stiind ca ab = -15
c) (a+b)(c-d) stiind ca ac = ad = bd=-5

Answer 1

a)5×(-100)=(-500)

b)ab+ac=(-15)+ac (despre c nimic ??)

c)ac-ad+bc-bd=(-5)+5+bc+5=bc+5 (la fel, despre bc ??)