In each of the Exercises 7 to 15, find the equations of the hyperbola satisfying the given conditions: vertices (± 7, 0), e = 4/3.
The equation of the hyperbola is or .
Explanation
This question tests understanding of hyperbola properties. Since vertices are at (±7, 0), the hyperbola has its transverse axis along the x-axis with center at origin. The value of a is determined from vertices, then eccentricity gives c, and finally b² is calculated using the hyperbola relationship c² = a² + b².
Solution Steps
Step 1: Since vertices are (±7, 0), the hyperbola has transverse axis on x-axis with a = 7 and a² = 49.
Step 2: Using eccentricity formula e = c/a, we get c = e × a = (4/3) × 7 = 28/3.
Step 3: For hyperbola, c² = a² + b², so b² = c² - a² = (28/3)² - 49 = 784/9 - 441/9 = 343/9.
Step 4: The standard equation of hyperbola with transverse axis on x-axis is x²/a² - y²/b² = 1.
Step 5: Substituting values: x²/49 - y²/(343/9) = 1 or equivalently x²/49 - 9y²/343 = 1.