Determine if Ordered pairs are Solutions:
-8x - 14y = 28
2x - 7y = 14

Find the value of the cosine for angle a

Agreeting card company can produce a box of cards for $7.50. if the initial investment by the company was $50,000, how many boxes of cards must be produced before the average cost per box falls to $10.50?

Measures of the angle of r, 31 s (x+4) t (3x+9)