Greatest common factor of 2x+8x?

Neveah and clint are baking muffins for the bake sale. they need to bake 30 muffins for their display case. clint has baked 4 so far, and neveah has baked 7. how many muffins (m) do they have left to bake? show your work!

Two cyclists 84 miles apart start riding toward each other at the samen time. one cycles 2 times as fast as the other. if they meet 4 hours later what is the speed (in miles) of the faster cyclists

What is the expression in factored form? -20x^2 - 12x a. 4x(5x+3) b. -4x(5x-3) c. -4(5x+3) d. -4x(5x+3)