If three empanadas and two drinks cost $9, and four empanadas and one drink costs $9.50, how much does a drink cost?

In the figure below, ∠dec ≅ ∠dce, ∠b ≅ ∠f, and segment df is congruent to segment bd. point c is the point of intersection between segment ag and segment bd, while point e is the point of intersection between segment ag and segment df. the figure shows a polygon comprised of three triangles, abc, dec, and gfe. prove δabc ≅ δgfe.

How do i put 3(x+7) in distributive property

Use sigma notation to represent the following series for 9 terms.