Answer:
11
Step-by-step explanation:

Answer:
(2 x +1) ( x + 1) = 2 x² + 3 x + 1
Step-by-step explanation:
The steops used to find the product of (2 x + 1) (x + 1) are
=( 2 x )× x + (2 x) × 1 + x + 1
= 2 x² + 2 x + x + 1
= 2 x² + 3 x + 1
Yes "3x8 = 4x6" does illustrate the commutative property of multiplication.
Area of rectangular post card = length x width
For the given post card:
length = 4 in
width = (3+b) in
area = 24 in^2
So, substituting in the equation of the area:
24 = 4 x (3+b)
24 = 12 + 4b
24 - 12 = 4b
12 = 4b
b = 3 in
Therefore:
the length of the postcard = 4 inch
the width of the postcard = b+3 = 3 + 3 = 6 inch