Expanding the left side of the equation:
(7x + 1)(3x - 1) - 21x^2= 7x 3x + 7x (-1) + 1 3x + 1 (-1) - 21x^2= 21x^2 - 7x + 3x - 1 - 21x^2= -4x - 1
Therefore, the equation simplifies to:
-4x - 1 = 3
Adding 1 to both sides:
-4x = 4
Dividing by -4:
x = -1
So, the solution to the equation is x = -1.
Expanding the left side of the equation:
(7x + 1)(3x - 1) - 21x^2
= 7x 3x + 7x (-1) + 1 3x + 1 (-1) - 21x^2
= 21x^2 - 7x + 3x - 1 - 21x^2
= -4x - 1
Therefore, the equation simplifies to:
-4x - 1 = 3
Adding 1 to both sides:
-4x = 4
Dividing by -4:
x = -1
So, the solution to the equation is x = -1.