Mariah purchases three hair barrettes by using a gift card, which has a balance of $35.79. which expression models her purchase?

3b-35.79
35.79+3b
35.79b-3
35.79-3b

you would use (d.) the law of cosines or a^2 = b^2 + c^2 – 2bc(cos a)

, b^2 = a^2 + c^2 – 2ac(cos b), or c^2 = a^2 + b^2 - 2ab(cos c). you wouldn't use b. the law of sines as it is mostly effective when 1side and 2angles are given. a and c aren't the answer for they are the improper versions of the law of cosines. hope this is .

can you add an image ?

step-by-step explanation: