(3 – 2*√7)*(3 + 2√7)
I think it is the multiplication symbol 2*√7 that is throwing me off.
2007-11-15 04:59:25 · 6 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
1. Write it on a piece of paper.
2. Place said paper into a piece of tin foil and wrap.
3. Preheat oven to 350°
4. Put paper in for 5-10 minutes.
5. Remove. It's been simplified to ash.
2007-11-15 05:03:29 · answer #1 · answered by Anonymous · 3⤊ 2⤋
This is pretty straight forward, although it looks a little freaky with the roots in there.
So just use the FOIL method like you normally would
First: 3*3=9
Outside: 3*2√7=6√7
Inside: -2√7*3=-6√7
Outside: -2√7*2√7=-4(7) Multiplying both square roots will eliminate the root, just as though the root has been squared.
So now we have:
9+6√7-6√7-4(7)
The 6√7-6√7 disappears, since one is positive, and one is negative.
So now we have:
9-4(7)
4*7 is 28
9-28=-19
2007-11-15 05:10:41 · answer #2 · answered by Anonymous · 0⤊ 0⤋
=3*3 +3*2√7 -2√7*3 -2√7*2√7
= 9 +6√7 -6√7 -28
= -19
2007-11-15 05:06:44 · answer #3 · answered by ironduke8159 7 · 0⤊ 0⤋
This given expression is in the form of (a-b)(a+b) , which is equal to
a^2 - b^2
here a = 3 and b = 2√7
so (3 - 2√7)(3 +√7) = 3^2 - (2√7)^2 = 9 - (28) = -19
2007-11-15 05:05:49 · answer #4 · answered by mohanrao d 7 · 0⤊ 0⤋
Multiply it out the root 7's get cancelled out you end up with a number if i remember right
2007-11-15 05:02:28 · answer #5 · answered by Deano 2 · 0⤊ 0⤋
I can't, I'm in a microwave.
2007-11-15 05:06:38 · answer #6 · answered by neohioguy1962 5 · 2⤊ 0⤋