Final answer:
To find the value of the unknown variable (l) in the formula A = lw, substitute the given values of A and w, then solve for l.
Step-by-step explanation:
To determine the value of the unknown variable (l), we can use the formula A = lw, where A is the area and w is the width. Given that A = 464 cm² and w = 4 cm, we can plug these values into the formula to solve for l.
Substituting the given values: 464 cm² = l × 4 cm
To isolate l, divide both sides of the equation by 4 cm: l = 464 cm² / 4 cm = 116 cm
Therefore, the value of the unknown variable (l) is 116 cm. Hence, the correct answer is (b) 116 cm.