Respuesta :

david's procedure is correct becsuse Keisha didnt put the correct value of sin theta in equation, she forgot to mention negative sign. though solution are same but in other case it could have gone wrong

Answer 1:

Option C - Both procedures are correct.

Step-by-step explanation:

As for Keisha's method of solving the question

  • Tan^2 Q + 1 = Sec^2Q
  • Sin^2 Q/ Cos^2 Q +1 = 1 / Cos^2 Q
  • (8/17)^2 / Cos^2 Q +  1 / Cos ^2 Q
  • Cos Q = +- Square root of 1 - 64/289
  • Cos Q = +- 15/17

Therefore, Keisha's procedure is correct

Answer 2:

Option C - Both procedures are correct.

Step-by-step explanation:

As for David's method of solving the question.

  • Sin^2 Q + Cos^2 Q = 1
  • Cos^2 Q = 1 - (-8/17)^2
  • Cos Q = +- Square Root of 225/289
  • Cos Q = +- 15/17

Therefore David's procedure is correct.