A train leaves the station at time t=0. Traveling at a constant​ speed, the train travels 420 kilometers in 3 hours. Answer parts a and b.

If square root x = -7, then x= -49 true or false

Aline passes through the point (–7, 5) and has a slope of 1/2 which is another point that the line passes through?

If you were constructing a triangular frame, and you had wood in the length of 4inches, 4 inches, and 7 inches, would it make a triangle? would you be able to create a frame from these pieces of wood? yes or no. explain your mathematical thinking