http://i40.tinypic.com/2rr49lc.png
^ questions in picture above
okay... as you can see, the answer is provided; but i truly need to know the steps to get to the answer... i'm a tad confused on the process... any help would be greatly appreciated (and, in turn, rewarded)
Thank you so much!
^ questions in picture above
okay... as you can see, the answer is provided; but i truly need to know the steps to get to the answer... i'm a tad confused on the process... any help would be greatly appreciated (and, in turn, rewarded)
Thank you so much!
-
1) sqrt(x^2+2)=sqrt(2x+5)
x^2+2=2x+5
x^2-2x-3=0
(x-3)(x+1)=0
so x=3 x=-1
Note you do have to be careful when squaring both sides of an equation as sometimes you introduce extra solutions that won't solve the original equation.
2) (x-4)^2+3(x-4)-18=0
x^2-8x+16+3x-12-18=0
x^2-5x-14=0
(x-7)(x+2)=0
x=7 or x=-2
3) x^(2/3)-4x^(1/3)+3=0 (Let y=x^(1/3))
y^2-4y+3=0
(y-3)(y-1)=0
y=3 or y=1
y^3=x so x=27 or x=1
x^2+2=2x+5
x^2-2x-3=0
(x-3)(x+1)=0
so x=3 x=-1
Note you do have to be careful when squaring both sides of an equation as sometimes you introduce extra solutions that won't solve the original equation.
2) (x-4)^2+3(x-4)-18=0
x^2-8x+16+3x-12-18=0
x^2-5x-14=0
(x-7)(x+2)=0
x=7 or x=-2
3) x^(2/3)-4x^(1/3)+3=0 (Let y=x^(1/3))
y^2-4y+3=0
(y-3)(y-1)=0
y=3 or y=1
y^3=x so x=27 or x=1