Find $$b$$ if $$\dfrac{x^2}{16}+\dfrac{y^2}{b^2}=8$$ passes through $$(8,10)$$
  • A
    5
  • B
    6
  • C
    7
  • D
    8

Solution

$$\dfrac{x^2}{16}+\dfrac{y^2}{b^2}=8\\\dfrac{8^2}{16}+\dfrac{100}{b^2}=8\\\dfrac{100}{b^2}=4\\b^2=25\\b=5$$