Answer:
The value of x is 6
Explanation:
The formula of the area of the rectangle is A = l × w, where
In the rectangle ABCD
∵ AB = 2x cm
∴ l = 2x
∵ AD = x cm
∴ w = x
→ Use the formula of the area above to find its area
∵ A = 2x × x
∴ A = 2x²
∵ The area of the shaded region = 50 cm²
→ When the shaded region removed, then the remaining area is the
unshaded region
∵ The area of unshaded region = 22 cm²
∵ The area the ABCD = area the shaded region + area unshaded region
∴ A = 50 + 22
∴ A = 72 cm²
→ Equate the two right side of A
∵ 2x² = 72
→ Divide both sides by 2
∴ x² = 36
→ Take √ for both sides
∴ x = 6
∴ The value of x is 6