Question

Can someone take me step by step in simplifying this?

Answer 1

#10 just add -2 plus 5 together which is 3 and then add 3i plus -2i together and you get I so the answer would be 3+i

Answer 2

alright and what about 15?

Answer 3

distributive property?

Answer 4

and also 17

Answer 5

one second im doing 15 right now :)

Answer 6

okay so it's not -6 +9i ?

Answer 7

no im sorry!

Answer 8

okay so what you do first is FOIL so you would do 2 times -3 (-6) then 2 times 6i (12i) then -i times -3 (3i) then -i times 6i (6i^2 or 6i squared) so you would have -6+12i+3i-6i squared. now you have to combine like terms but since you have -6i squared an i squared is basically a -1 so that -6i squared terns into a positive 6 because -6 times -1 is 6. so now you combine like terms and the answer would be 15i because a -6+6 is 0.

Answer 9

oh okay:) thanks! and what about #17?

Answer 10

for 17 you just rewrite it as (-1+3i)(-1+3i) because by squaring it, it just means its written twice. and then you now do what you did for #15 FOIL then combine like terms. so you would have 1-3i-3i+9i squared. again i squared represents a -1 so you would then have 1-3i-3i-9 because 9 times a -1 is -9. so the answer would be -8-6i.

Answer 11

alright! thank you! i also need help with quadratic formula and it involves square rooting a negative

Answer 12

okay, i will try my best!

Answer 13

\[2x ^{2} - 3x + 5 = 0\]

Answer 14

are you saying you have to use quadratic formula to solve this?

Answer 15

yes!:)

Answer 16

okay give me a second!

Answer 17

\[-b \pm \sqrt{b ^{2}-4AC} \over 2A\]

Answer 18

yeah i know it :)

Answer 19

Okay:)

Answer 20

okay so my teacher taught me to write about a, b, and c so i don't get confused so a=2 b=-3 and c=5 so you would plug in these numbers into the equation. so you would get \[3\pm \sqrt{9-4(2)(5)}\]

Answer 21

all over 4

Answer 22

that is your first step

Answer 23

okay, the only thing i dont get is the "i" part

Answer 24

then after that you would get \[3\pm \sqrt{-31} \over 4\]

Answer 25

and no perfect squares can go into 30 and you cant have a negative inside the square root and that is what i represents so the answer would be \[3\pm i \sqrt{31} \over 4\]

Answer 26

okay:)

Answer 27

technically the correct way to write it is (3/4) plus or minus i squre root of 31 over 4. so you just separate them since they have the same denominator