Respuesta :

3px = 2q(r-5x)
distribute
2qr - 10qx
3px = 2qr - 10qx

To solve for x
add 10qx to both sides
3px + 10qx = 2qr
factor out x
x(3p+10q) = 2qr
divide both sides by 3p+10q to isolate x
x = 2qr / (3p+10q)

Hope this helps :)