How do you simplify #-4(-3i)(-5+7i)#?
1 Answer
Aug 7, 2016
Explanation:
#-4(-3i)=12i#
#rArr12i(-5+7i)=-60i+84i^2#
#color(orange)"Reminder" color(red)(|bar(ul(color(white)(a/a)color(black)(i^2=(sqrt(-1))^2=-1)color(white)(a/a)|)))#
#rArr-60i+84i^2=-60i-84#
#rArr-4(-3i)(-5+7i)=-84-60i#
