Solution for Problem 1.3.3

 Solve for x:  (x – 4)2 = 5      Square Root Method

Solve

Step
Take square root of both sides
ADD 4 from both sides
Approximations... Remember, you have 2 answers.
x ≈  4 + 2.236 = 6.236
x ≈  4 – 2.236 = 1.764

Check 

If x  = 6.236, then
 (6.236 – 4)2 = 5
  (2.236)2 = 5
4.999696 ≈ 5 
 **Rounding error

If x  = 1.764, then
 (1.764 – 4)2 = 5
  (-2.236)2 = 5
4.999696 ≈ 5