Evaluate the limit of (x^2 - 25)/(x - 5) as x approaches 5.
Answer and explanation
Correct answer: C. 10
- Step 1: Factorise the numerator: x^2 - 25 = (x - 5)(x + 5). Step 2. Cancel (x - 5): the limit of (x + 5) as x approaches 5 is 10. Answer: 10. Why not the others: 0: Direct substitution gives 0/0, which is indeterminate, not 0. 5: That is the value of x at the limit, not the limit of the expression. 25: That is the square of the number, not the limit.
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