Hey, is this point the so-called plumb line of the pyramid?

The price of a good produced by us depends on the quantity x according to the following function P(x)=10000-100x The resulting costs are K(x)=50000+300x Create the profit function: (10000-100x)x-(50000+3000x) 10000*-1=-10000x -100x*-1 = -100x 50000*-1=-50000 -1*=3000x= 3000x G(x)= 10000x-100x²-5000+3000x | add 10000x+3000x G(x)=-100x²+13000x-5000