Answer:
x = √71 - 8
x = -√71 - 8
Step-by-step explanation:
x-intercept for the equation using completing the square.
x² + 16x - 7 = 0
- transpose 7 to right side : x² + 16x = 7
by completing the square:
write in the form of x² +2ax + a² = (x + a)²
- solve for a : 2ax = 16x
- a = 16x/2x
- a = 8
back to first equation, we add a² = 8² to both sides
- x² + 16x + 8² = 7 + 8²
- simplify: x² + 16x + 8² = 71
- complete the square: (x + 8)² = 71
solve x + 8 = √71
x = √71 - 8
x = -√71 - 8
therefore, the answer would be:
x = √71 - 8
x = -√71 - 8
