I have to figure out how to do this by using the fractional exponents, not by converting the first terms to a cube root. If anyone can help me figure this out, I would appreciate. This is not some attempt at homework help, so please no "Do your own homework" wisecracks. I am reading a book on algebra and it doesn't explain how to do this.
2006-10-31 17:09:37 · 3 answers · asked by FoxBarking 3 in Science & Mathematics ➔ Mathematics
Why it's quite simple
(4w+5)^1/3=-3
4w+5=-3^3 (Cube both the sides)
4w + 5 = -27
4w = -27-5
4w = -32
w = -32/4
w = -8
Check the solution:
[(4*-8) + 5] ^1/3 = (-32+5)^1/3
= -27^1/3
= -3
The answer is correct.
2006-11-01 00:24:01 · answer #1 · answered by Akilesh - Internet Undertaker 7 · 0⤊ 0⤋
cube both Left hand side and right hand side.
{(4w+5)^}^3 = (-3)^3
4w+5 =-27
4w= -27-5
4w=-32
w=-8.
Now substitute w = -8 in the original eqn,
(4(-8)+5)^1/3
=(-32+5)^1/3= -3
2006-11-01 01:17:52 · answer #2 · answered by Jaaji 2 · 0⤊ 0⤋
Well how I would do it is like this:
(4w+5)^(1/3)=-3
[(4w+5)^(1/3)]^3=(-3)^3
4w+5=-27
4w+5-5=-27-5
4w= -32
4w/4= -32/4
w= -8
2006-11-01 01:17:50 · answer #3 · answered by daniel_oobladee 2 · 1⤊ 0⤋