Final answer:
The problem presented seems to require finding the value of x by equating the perimeters of a rectangle and a trapezium. However, there's insufficient information provided in the question as it includes an undefined value 'r', preventing us from solving for x without more context or additional equations relating r and x.
Step-by-step explanation:
The question involves finding the value of x when the perimeters of a rectangle and a trapezium are given to be the same. To begin solving the problem, let's sum up the sides of the rectangle ABCD, knowing that opposite sides of a rectangle are equal:
- AB + BC + CD + DA = 2(AB) + 2(BC)
- (3r + 4) + (5x) + (3r + 4) + (5x) = 2(3r + 4) + 2(5x)
- 6r + 8 + 10x
Now, let's find the sum of the sides of the trapezium EFGH:
- EF + FG + GH + HE
- (x - 3) + (4x) + (7x - 3) + (5x)
- x - 3 + 4x + 7x - 3 + 5x
- 17x - 6
Since the perimeters are the same, we can set them equal to each other: