Question

what is √x+8=x-4

A.8
B.-1
C.-4,4
D. no real solution

Answer 1

Is the sq root over the x or x+8

Answer 2

x+8

Answer 3

I get x = 16....not one of your choices. OK that makes sense

Answer 4

I get A. Do you want to see how to do this?

Answer 5

yes

Answer 6

You really need to stop giving away answers ._.

Answer 7

√(x+8)=x-4
square both sides, get
x+8 = x^2 - 8x + 16
simplify by combine similar terms, get
x^2 - 9x + 8 = 0
factor out above,
(x-1)(x-8) = 0
setting each factor equals zero

x-1=0
then x = 1

x-8=0
then x=8

we must recheck again, if x=1 and x=8 is right

√(x+8)=x-4
put x=1, get
√(1+8) = 1-4
3 = -3
this is false

√(x+8)=x-4
put x=8
√(8+8)=8-4
4 = 4
nah, this is true

so, only x=8 as the solution

Answer 8

does that make sense, @karlisa1604 ?

Answer 9

Yes. Thank you

Answer 10

you're welcome