Help now!!

[g1sk8terz]

SOlve for X... i can't get it

Square rooot of (x+7) = -x^2+5

thanks

 

[Denis]

SOlve for X... i can't get it
Square rooot of (x+7) = -x^2+5
thanks

I'll assume the right side should be -x + 5 ; if not, then you're dealing with x^4:
after squaring, you have: x^4 - 10x^2 - x + 18 = 0

sqrt(x + 7) = -x + 5 ; square both sides to get:
x + 7 = x^2 - 10x + 25
x^2 - 11x + 18 = 0
(x - 9)(x - 2) = 0
x = 9 or x = 2

 

[g1sk8terz]

no, the right side is -x^2 + 5......unless the book misprinted it....do you know how to solve it if the right side is -x^2 + 5??

 

[stapel]

I could be wrong, but I don't see that the equation has any rational solutions, if the right-hand side really contains x².

Eliz.

 

[g1sk8terz]

thanks. ill double check with my teacher 2morro to see if it is indeed a misprint in my text book

 

[Denis]

As example, x = 1.446941~ is a solution to x^4 - 10x^2 - x + 18 = 0;
but are you at that stage yet: solving level 4 equations?

 

[g1sk8terz]

im in acc precalc n we just started...mostly review stuff from last year and that was one of my problems for homework..but im going to ask about it today if there's a misprint