PLEASE HELP! URGENT. the law of cosines is a2+b2-2abcosC=c2. Find the value of 2abccosC.

If the cost to mail a package is an initial $5 and $0.28 for every pound the total cost to mail a package was $11.27, how much did the package weigh?

The distance of a chord from the centre of a circle is 12cm and the lenght of the chord is 10cm. find the radius of the circle

Rewrite the following quadratic functions in intercept or factored form. show your work. y = 4x^2 - 19x- 5