For each quadratic equation below, predict which factoring method would be the best choice to use, then solve each equation using 3 different factoring methods. Lastly, explain which method WAS the best choice.
A. x^2 + 4x -21
B. x^2 - 8x +13

2x + 1 < 5 solve the following inequality. then place the correct number in the box provided.

Four individuals pool money together to start a new business and agree to split the profits equally. n invests $6,000, x invests $2,000, y invests $8,000 and z invests $4,000. if the profits for the first month were $100,000, y receives than if the profits were divided in proportion to how much they invested.

Geometry in the diagram, ∠abc is a right angle. ∠dbc = 30°27'40". find the measure of ∠abd.