Solve the system of linear equations by substitution.
2x + y = 4
-x + 3y = -9

Your friend swims on the school team. in his first four races, his times are 24.7, 23.5, 25.6, and 27.2 seconds. which time listed for his next race would make the range larger?

What is the name of a polygon that has four congruent sides and theses angle measures 60,120,60,120?

Can someone me with my math problems i have a bunch. i will give brainliest and lots of pleeeaaasssee