Answer
True
The trinomial that models the area of the larger garden is $9x^{2}+ 15x - 14$ square feet
Work Step by Step
Area of the Square Garden $ a^{2}= 9x^{2}$ where a is side of the square garden.
Therefore, Side (a) $ = \sqrt (9x^{2})$ $= 3x$
One side is made 7 feet longer, then $ l = 3x+7$
Other side is made 2 feet shorter then $b = 3x-2$
Area of the larger garden = $l \times b$
$= (3x + 7)(3x - 2)$
$= 3x.3x -3x.2 + 7.3x -7.2$
Multiply coefficients and add exponents
$= 9x^{2} - 6x + 21x -14$
Combine like terms.
$= 9x^{2} +(-6 + 21)x -14$
$= 9x^{2} + 15x -14$
The trinomial that models the area of the larger garden = $9x^{2}+ 15x - 14$ square feet