
Patrick B. answered 04/26/19
Math and computer tutor/teacher
The statement, as written, is completely FALSE.
Here is a counter example.
For a=0 and b=sqrt(2),
2*a+2*b + 1 = 2*sqrt(2) + 1
2*a +2*b - 1 = 2*sqrt(2) - 1
Multiplying them: 8 - 1 = 7
Then the quadratic equation becomes:
x^2 + 2x = 7
x^2 - 2x - 7 = 0
Quadratic formula says:
[2 +or- sqrt( 4 - 4*-7) ]/ 2
[2 +or- sqrt( 4- -28)] / 2
[ 2 +or- sqrt(32)] / 2
[2 +or- 4*sqrt(2)]/2
1 +or- 2*sqrt(2)
The solution is IRRATIONAL and not an integer.
Please repost with the correct statement of the problem.