Write an expression in terms of x to represent the area of parallelogram PQRS

The value of b is 5 if the parallelogram is a rectangle

Step-by-step explanation:

Mathematically, the diagonals of a rectangle are equal in value

Thus, for the given expressions to represent the diagonals of a rectangle, the two must be equal

To get the value of b that makes the two equal, we simply equate the two expressions

We have this as;

10/12(24b/5 - 36/5) = 2/3 (3b + 6)

opening the brackets, we have;

4b - 6 = 2b + 4

4b - 2b = 4 + 6

2b = 10

b = 10/2

b = 5

40 is the final : )