You have done the right step, check your answers after you have squared each side of an equation.
Take a simple case of
x=-4
square both sides,
x²=(-4)²=16
x=√16=±4
check:
x=-4 OK
x=+4 not a solution.
In your case, the solution of 73.126° is correct. The other one is false.
Ok, i did this maths trigo question, that says sinx-cos=2/3. I squared it on both sides to get sin2x=5/9 and did the sum. In the end i got two solutions, 16.9 and 73.1. However, when i substituted the answers back into the equation, only one of the 2 answers was correct! The other one didn't work out! Why is this so? I'm pretty sure both answers are correct, so what's going on? Please help!
1 answer
1 answer