Explanation:
1. rectangle
A = l × w
= (3x + 1) (2x - 3)
= 6x² - 7x - 3 in²
2. square
A = s × s
= (3x) × (3x)
= 9x² ft²
3. triangle
(x + 3) + (x - 4) + (2x + 5)
= 4x + 4 m
4. square
perimeter = 4 × s
= 4 × 4x ft
= 16x ft
5. rectangle
perimeter = 2 ( w + l)
= 2 (x + x + 4)
= 2 (2x + 4)
= 4x + 8 in