This is kinda tricky to explain since it has a squre root in it...
(4 - 3 square rt symbol 7)(5 + 2 square rt symbol 7)
make sense?
2006-12-10 06:59:57 · 7 answers · asked by crazylifer 3 in Science & Mathematics ➔ Mathematics
(4 - 3√7)(5 + 2√7)
= 20 + 8√7 - 15√7 - 6(√7)(√7)
= 20 - 7√7 - 42
= -22 -7√7
2006-12-10 07:02:42 · answer #1 · answered by Jim Burnell 6 · 1⤊ 0⤋
Yes, its easy and makes sense. I am just not sure if you mean symbol multiplied by 7, or just a symbol, or simply 7. In any case I will just let anything under the root as X, and you replace it with whatever you want.
(4 - 3âX)(5 + 2âX) = (4x5) + (8âX) - (15âX) - (6X)
= 20 - 7âX - 6X
2006-12-10 15:08:38 · answer #2 · answered by Max D 3 · 0⤊ 0⤋
(4 - 3â7)(5 + 2â7) =
20 - 15â7 + 8â 7 - 6(â7)(â7) =
20 - 7â7 - 6â49 =
20 - 7â7 - 6 x 7 =
20 - 7â 7 - 42 =
- 22 - 7 â7
- - - - - - - -s-
2006-12-10 16:26:19 · answer #3 · answered by SAMUEL D 7 · 0⤊ 0⤋
(4 - 3 sqrt(7)) (5 + 2 sqrt(7))
4 * 5 + 4*2 sqrt(7) - 3*5 sqrt(7) - 3*2 * 7
20 + 8 sqrt(7) - 15 sqrt(7) - 42
-22 - 7 sqrt(7)
2006-12-10 15:03:35 · answer #4 · answered by Uther P 1 · 1⤊ 0⤋
(4 - 3root7)(5 + 2root7)
use FOIL:
4*5 + 4*2root7 - 3root7*5 - 3root7*2root7
= 20 + 8root7 - 15root7 - 6*7
= 20 - 7root7 - 42
= -22 - 7root7
2006-12-10 15:03:52 · answer #5 · answered by Alex 2 · 1⤊ 0⤋
Multiply by FOIL first, outside, inside, last. Then group like terms and simplify
2006-12-10 15:02:26 · answer #6 · answered by nckobra40 3 · 0⤊ 0⤋
no. but i'm only in algebra 1.
2006-12-10 15:03:14 · answer #7 · answered by cocoa_spark 2 · 0⤊ 2⤋