Question 160328
It's a very good idea to use proofs for ALL answers.
x - 3 (sqrt(x)) - 4 = 0
Let x=1:
Proof:
x-3sqrtx-4=0
1-3sqrt1-4=0
1-3*1-4=0
1-3-4=0
1-7=0
-6=0 not a valid proof.
Let x=-1
-1-3sqrt-1-4=0
1-3*i-4=0
-3-3i=0 not a valid proof.
Proof for x=16:
16-3sqrt16-4=0
16-3*4-4=0
16-12-4=0
16-16=0
0=0 a valid proof.