Answer:
A. A=12x(2x−1);248cm2
Explanation:
The complete question is
The height of a triangle is 1 cm less than twice the length of the base. Let x = the length of the base. Write a function rule for the area of the triangle and determine the area if the length of its base is 16 cm.
A. A=12x(2x−1);248cm2
B. A=12xh;128cm2
C. A=12x(x−2);112cm2
D. A=122x(x−1);240cm2
The area of a triangle is defined as

Where
is the base and
is the height.
According to the problem, the height is 1 cm less than twice the base, that is

Now, replacing the second relation in the area equation, we have

If
we have

So, the area is 248 square centimeters.
Therefore, the right answer is A.