Question

Solve x² – 4 = 77. What are the possible values of x?

1) x = 9 or x = -9
2) x = 11 or x = -7
3) x = 9i or x = -9i

Answer 1

The equation x² – 4 = 77 can be solved by rearranging the equation and taking the square root of both sides, yielding the solutions x = 9 or x = -9.

Step-by-step explanation:

To solve the equation x² – 4 = 77, let's first move all terms to one side of the equation to set it equal to zero, and then solve for x:

1. Add 4 to both sides of the equation: x² = 77 + 4
2. Simplify the right side: x² = 81
3. Take the square root of both sides: x = ±√81
4. Since the square root of 81 is 9, the possible values of x are 9 or -9.