If the function f is given by f(x)=2x2−4, then which of the following represents the value of c such that f(c)=28? select one: a. 0 b. 2 c. 4 d. 8

C

given f(x) = 2x² - 4 , then

f(c) = 2c² - 4 = 28 (add 4 to both sides )

2c² = 32 ( divide both sides by 2 )

c² = 16 ( take the square root ob both sides )

c = ± = ± 4

Since the answer is looking for the positive solution then c = 4

56.6

step-by-step explanation:

the ratio of the perimeters is equal to the scale.

the ratio of the areas is equal to the square of the scale.

34 / 20 = k

a / 19.6 = k²

substituting:

a / 19.6 = (34 / 20)²

a = 19.6 (34 / 20)²

a ≈ 56.6

correct answers below: