Question

The area of a lot is 4a2 – 225 square meters, if the length is 2a + 15 meters what is the width of the lot?

Answer 1

Answer:

Width of the lot $=2a - 15$ meters

Step-by-step explanation:

$4a^2 - 225$

$=(2a)^2 - (15)^2$

$=(2a + 15)(2a - 15)$  [using the identity $a^2 - b^2 = (a + b)(a - b)$]

Width of the lot $=\frac{Area}{Length}$

$=\frac{4a^2 - 225}{2a + 15}$

$=\frac{(2a + 15)(2a - 15)}{(2a + 15)}$

$=2a - 15$ meters