Expanding the expression:
(5x - 6)(5x + 6) - 25x * (x - 3)
= 5x 5x + 5x 6 - 6 5x - 6 6 - 25x x + 25x 3
= 25x^2 + 30x - 30x - 36 - 25x^2 + 75x
Combining like terms:
= 0 + 75x - 36
= 75x - 36
Therefore, (5x - 6)(5x + 6) - 25x * (x - 3) simplifies to 75x - 36.
Expanding the expression:
(5x - 6)(5x + 6) - 25x * (x - 3)
= 5x 5x + 5x 6 - 6 5x - 6 6 - 25x x + 25x 3
= 25x^2 + 30x - 30x - 36 - 25x^2 + 75x
Combining like terms:
= 0 + 75x - 36
= 75x - 36
Therefore, (5x - 6)(5x + 6) - 25x * (x - 3) simplifies to 75x - 36.