find all the solutions/values of the ff. probs: (value/s of x)
1) x + x^(1/2) = 20
2) cube root of x^2 - 1 = x - 1
3) x^-4 - 13x^-2 + 36 = 0
4) (square root of 8x + 7) - x = 0
5) (square root of 11-x) - (square root of x+6) = 3
6) 3(x+3) + (square root of x+3) = 2
Thanks
2007-07-10 13:25:15 · 5 answers · asked by rock-onz 1 in Science & Mathematics ➔ Mathematics
For the first one, I would isolate the square root and then square both sides to get a quadratic equation to solve by factoring or formula.
x^(1/2) = sqrt x..easier to write!
sqrt x = 20 - x now square both sides
x = (20 - x)^2
x = 400 - 40x + x^ 2
0 = x^2 - 41x + 400
This you can solve using the quadratic formula or by factoring.
0 = (x - 25)(x - 16)
x = 25 or x =16
I would use this procedure on the others as well. Isolate the sqrt or separate them when there is 2 and then square both sides.
2007-07-10 13:38:26 · answer #1 · answered by keely_66 3 · 0⤊ 0⤋
1.) 16
2.) 1
2007-07-10 20:35:06 · answer #2 · answered by jsardi56 7 · 0⤊ 0⤋
I havn't learned that stuff yet...sorry
2007-07-10 20:27:54 · answer #3 · answered by Anonymous · 0⤊ 0⤋
i dont have the time
2007-07-10 20:27:49 · answer #4 · answered by Jeeba 2 · 0⤊ 1⤋
dude this is not hard- just use your mind.
2007-07-10 20:28:31 · answer #5 · answered by Josee G 2 · 0⤊ 1⤋