Explanation:
We have (x + 4)(x + 2)cm² = 3cm².
=> x² + 6x + 8 = 3
=> x² + 6x + 5 = 0
=> (x + 5)(x + 1) = 0
=> x = -5 or x = -1
x = -5 is rejected as both side lengths would have negative values.
Therefore x = -1;
- (x + 4)cm = (-1 + 4)cm = 3cm
- (x + 2)cm = (-1 + 2)cm = 1cm
Hence the dimensions are 3cm by 1cm.