Question 65032
49z^2-42z+9 the answer is (7z-3)^2 how in the world do they come up with that?
49z^2-42a+9 is a perfect trinomial square
The 1st and 3rd terms are perfect squares
The 2nd term is -2 times the product of the square roots of the 1st and 3rd terms.
The factors are:
(7z-3)(7z-3) or (7z-3)^2
To see that this is true use FOIL to multiply (7z-3)(7z-3)
Cheers,
Stan H.