How do you write negative 4 tenths as a fraction?

Karen will divide her garden into equal parts. she will plant corn in 8/12 of the garden. what is the lowest number of parts she can divide her garden into?

In the diagram, ab is tangent to c, ab = 4 inches, and ad = 2 inches. find the radius of the circle.

If you were constructing a triangular frame, and you had wood in the length of 4 inches, 4 inches, and 7 inches, would it make a triangle? would you be able to create a frame from these pieces of wood?