Determine if the relation represents a function. explain

Amerchant has coffee worth $60 a pound that she wishes to mix with 50 pounds of coffee worth $90 a pound to get a mixture that she will sell for $70 a pound. how many pounds of the & 60 coffee should be used?

Cos^2x+cos^2(120°+x)+cos^2(120°-x)i need this asap. pls me

Talia grouped the terms and factored out the gcf of the groups of the polynomial 15x2 – 3x – 20x + 4. her work is shown below. (15x2 – 3x) + (–20x + 4) 3x(5x – 1) + 4(–5x + 1) talia noticed that she does not have a common factor. what should she do?