Answer:
k = 3.5
Step-by-step explanation:
Area of a rectangle = length × width
Area of the bigger triangle - Area of the smaller triangle = 35 cm²
Thus:
(2k + 6)(k) - (3)(k) = 35 cm²
2k² + 6k - 3k = 35
2k² + 3k - 35 = 0
Factorise
2k² + 10k - 7k - 35 = 0
2k(k + 5) -7(k + 5) = 0
(2k - 7)(k + 5) = 0
2k - 7 = 0
2k = 7
k = 3.5
Or
k + 5 = 0
k = -5
The value of k would be the positive number which is 3.5.
