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How do you simplify this: (4-8i)(-7+i)?
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High School Teacher
Use FOIL (first outer inner last) or distributive property
First `4*-7 = -28`
Outer `4*i = 4i`
Inner `-8i*-7 = 56i`
Last `-8i*i = -8i^2`
however `i^2 = -1`
therefore `-8i^2= +8`
add everything together by combining like terms
Posted by baxthum8 on August 20, 2013 at 12:12 AM (Answer #1)
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