Answer:
The dimensions of the rectangle in terms of x are (x+6) and (x-3).
Explanation:
The area of the triangle = LENGTH X WIDTH
Now, here the given expression for area is
![x^(2) + 3x -18](https://img.qammunity.org/2020/formulas/mathematics/middle-school/vv6oz2776c9g0re7di5350gg4asc8ox7rh.png)
Factorize the given expression, we get
![x^(2) + 3x -18 = x^(2) + 6x -3x -18](https://img.qammunity.org/2020/formulas/mathematics/middle-school/jttlmszf6cpd6bjh5efa8ul9tagdba1h3z.png)
or,
![x^(2) + 6x -3x -18 = 0](https://img.qammunity.org/2020/formulas/mathematics/middle-school/k7bjnb026c8wqm41otoqepv5187n1kb30m.png)
⇒
![x(x+6)-3(x+6) =0](https://img.qammunity.org/2020/formulas/mathematics/middle-school/isz1zh3h3i8m7dj5jewkn5q07i02flq5t5.png)
⇒
![(x+6)(x-3) =0](https://img.qammunity.org/2020/formulas/mathematics/middle-school/fqqr7k4j7zzhkwqb5wsntirwez2mqdzi5v.png)
So, the given area expression
![x^(2) + 3x -18 = (x+6)(x-3)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/z3pdb78up19bfcry37xx5p85atxi57t40m.png)
Hence, the dimensions of the rectangle are (x+6) and (x-3).