Find the perimeter of the polygon with vertices of a(0, 0), b(4, 0) and c(2, 3). round to the nearest tenth. just enter one number as your answer.

11.2

Since we have 3 vertices, we have a triangle. The sides are AB, BC, and AC. Using the Pythagoras's theorem, we can calculate the length of each side. 
Side AB is from (0,0) to (4,0) = length of 4.Side AC is from (0,0) to (2,3) = sqrt(2*2+3*3) = sqrt(13) = 3.6056Side BC is from (4,0) to (2,3) = sqrt((4-2)^2 + 3*3) = sqrt(13) = 3.6056
Add together 4, 3.6056, and 3.6056 giving 11.2112. Rounding to the nearest tenth, gives 11.2