Answer:
the answer is y=-0.556·x+7
A perfect square trinomial is found in the expression where both the leading coefficients and the constant are both perfect squares. That only is the case with the third choice above. 16 is a perfect square of 4 times 4, and 9 is a perfect square of 3 times 3. We need to set it up into its perfect square factors and FOIL to make sure, so let's do that. Not only is 16 a perfect square in that first term, but so is x-squared. Not only is 9 a perfect square in the third term, but so is y-squared. So our factors will look like this:
(4x + 3y)(4x + 3y). FOIL that out to see that it does in fact give you back the polynomial that is the third choice down.
The algebraic expression is 6(x+2)
