Show all work to multiply quantity 2 plus the square root of negative 25 end quantity times quantity 4 minus the square root of negative 100 end quantity

Question

darkknight · Answer

can you use the eqn tool to write out all that above first?

Tyrion · Answer

attachment

darkknight · Answer

do yk foil?
first, outer, inner, last

Tyrion · Answer

no

darkknight · Answer

the way it works is like this
You have other terms in your problem but ill use a, b, c and d
$$(a+b)(c+d)$$
outer, multiply a and c, first
then a and d
then b and c
then b and d
$$ac+ad+bc+bd$$
ill draw this as well

Tyrion · Answer

i thought u find the square root of the numbers first

darkknight · Answer

no need to do that, first foil then simplify, so yk how to foil now?

Tyrion · Answer

ima try it

Tyrion · Answer

aye @darkknight how u do 2 times square root of -25

Tyrion · Answer

would u simplify first

darkknight · Answer

why r u doing 2 time square root of -25?
foil
you multiply the first terms 
then the outer, then inner
then last

Tyrion · Answer

yes for a times b its 2 and sqaure root -25 right

darkknight · Answer

darkknight wrote:

the way it works is like this You have other terms in your problem but ill use a, b, c and d $$(a+b)(c+d)$$ outer, multiply a and c, first then a and d then b and c then b and d $$ac+ad+bc+bd$$ ill draw this as well

there is no a times b, you never multiply 2 numbers that are in the same set of parenthesis when expanding

Tyrion · Answer

ohh i read it wrong my bad

darkknight · Answer

ur good

Tyrion · Answer

so it would be 2 times square root -100??

Tyrion · Answer

it says dats 20 i

darkknight · Answer

first 2 times 4, remember foil, the first terms first
then yes 2 times sqrt -100, which is 20i, 
keep g oing

Tyrion · Answer

yuh i did the first one already im juss kurious on wat the i is

Tyrion · Answer

lool

darkknight · Answer

yeah sure,
$i=\sqrt{-1}$
you cant take the square root of a negative number (as a real number) so its imaginary. the sqrt of a negative number isn't a real number, leave it how it is and keep going with the problem, it might cancel later on

Tyrion · Answer

i understand wat u sayin

darkknight · Answer

alr sweet, now move to the inner terms and last

Tyrion · Answer

@snowflake0531 do uk wats next after i did the multiply stuff

snowflake0531 · Answer

So do you have (2+ isqrt25)(4- isqrt100)?

Tyrion · Answer

yuh and i did the foil method so wats next

snowflake0531 · Answer

Well, write out what you have

snowflake0531 · Answer

Also btw you can simplify it to (2+5i)(4-10i)

Tyrion · Answer

AxC=8
AxD=20i
BxC=20i
BxD=-50

Tyrion · Answer

i thought i was suppose to simplify yesterday dark showed me dis way

snowflake0531 · Answer

You're doing it wrong, 2 values are incorrect $$(2+5i)(4-10i) = 8 -20i + 20i + 50$$

Tyrion · Answer

whikh ones

Tyrion · Answer

and dats not a positive 50 its negative

Tyrion · Answer

nor is the first 20i dat was a positive too

snowflake0531 · Answer

No, one is positive one is negative

snowflake0531 · Answer

-10i(2) and 4(5i)

snowflake0531 · Answer

And btw sorry I didn't get the notifs

Tyrion · Answer

im gettin too konfused gettin 2 ways told to me

snowflake0531 · Answer

No, we're using the same method, FOIL

Tyrion · Answer

ima juss figure it out on my own

Tyrion · Answer

@darkknight

darkknight · Answer

snowflake0531 wrote:

You're doing it wrong, 2 values are incorrect $$(2+5i)(4-10i) = 8 -20i + 20i + 50$$

read this, I think you may have forgotten the negative sign before the sqrt(-100) in your problem it says 4 minus (sqrt(-100))

Tyrion · Answer

OHHHH i forgot to keep the minus,,so rlly its 8 plus 50??

Tyrion · Answer

kause the 2 insides kankel out

darkknight · Answer

tyrion wrote:

OHHHH i forgot to keep the minus,,so rlly its 8 plus 50??

yea, and you can simplify 8 and 50 also

darkknight · Answer

tyrion wrote:

kause the 2 insides kankel out

correct

Tyrion · Answer

so the answer is 58 or no

1 attachment