Question #2: pls help show work due soon mate

In the proof of the triangle angle sum theorem, you must draw an auxiliary line. which construction must you use to draw this line?

Can someone answer it, and plot it, for 20 points and brainliest answer? p.s. they're the same ! : )

The function a represents the cost of manufacturing product a, in hundreds of dollars, and the function b represents the cost of manufacturing product b, in hundreds of dollars. a(t) = 5t + 2 b(t) = 7t - 2t +4 find the expression that describes the total cost of manufacturing both products, a(t) + b(t). a. 7t^2 - 7t + 2 b. 7t^2 + 3 +6 c. 7t^2 + 7t - 6 d. 7t^2 - 3t + 6