Which system of linear equations can be solved using equation [[x],[y]]= [[(1)/(4),(3)/(4)],[1,2]][[28],[-12 ]]

If u give wrong answer ill report u : )

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!

Jack did 3/5 of all problems on his weekend homework before sunday. on sunday he solved 1/3 of what was left and the last 4 problems. how many problems were assigned for the weekend?