Solve the equation x3 x2 5 Be sure to check for extraneous
Solve the equation (x-3) + (x+2) = 5. Be sure to check for extraneous solutions.
Solution
Given that
(x-3) + (x+2) = 5
(x-3) = 5 - (x+2)
Squaring on both sides of equation
[ (x-3) ]2 = [ 5 - (x+2) ]2
x - 3 = 52 + [ (x+2) ]2 - 2 .5 .(x+2)
x - 3 = 25 + (x +2) - 10 (x+2)
10 (x+2) = 25 +x +2-x+3
10 (x+2) = 30
(x+2) = 30 / 10
(x+2) = 3
x + 2 = 32
x = 32 - 2
x = 7
Check for x = 7 in given equation
(x-3) + (x+2) = 5
(7-3) + (7+2) = 5
4 + 9 = 5
2 + 3 =5
5 = 5
The solution is valid
A solution of a simplified version of an equation that does not satisfy the original equation,that solution is called extraneous solution.
Therefore,
x = 7 is not extraneous solution

