Answer:
see explanation
Explanation:
Given
AB + BC = 31
AB - BC = 17
Add the 2 equations
2AB = 48 ( divide both sides by 2 )
AB = 24
Substitute AB = 24 into the first equation
24 + BC = 31 ( subtract 24 from both sides )
BC = 7
Using Pythagoras' identity to find the hypotenuse AC
AC² = AB² + BC² = 24² + 7² = 576 + 49 = 625 ( take square root of both sides )
AC =
= 25
Then
sinA =
=
=

cosA =
=
=

sinC =
=

cosC =
=
