The correct answer is B.
Determine and recall first the trigonometric functions:
Sin A = Opposite/Hypotenuse
Cos A = Adjacent/Hypotenuse
Tangent = Opposite/Adjacent
If for example we try to take an angle, for example the Y, then Y is opposite Y. The Hypotenuse will be the longer side which is going to denoted by X and the next side will be Adjacent which will be denoted by Z.
Use this test to answer:
Sin Y = Y/X
where:
Y = opposite
X = hypotenuse
Cos (90 - y) = cos (90 - 50) = cos 40
where Z = 40
we look for cos Z = Y/X
Therefore,
Sin Y = Cos (90 - Y)
You have 90 and you have 15%
so you have to subtract 90 and 15%
90-15%=76.5
she puts $13.50 in savings and is able to spend $76.5
