How do you simplify #(10i)*-7+(4i)#?

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Answer 1 · 2018-07-11T03:58:30

Case -1 # 10i * (-7 + 4i) = -40 - 70i#

Case 2 # (10i * -7) + 4i = - 66 i #

Case 1 : #10 i * (-7 + 4i)#

#=> (10i * -7 ) + (10 i * 4 i)#, removing bracket and regrouping

#=> -70 i + 40 i^2#, multiplying

#=> -40 - 70 i#, simplifying, as #i^2 = -1#

Case 2 : #(10i * -7) + 4i#

#=> -70i + 4i#

#=> - 66i#