When there is an initial new investment into an economy it will create new spending and jobs.
Workers will be taken on directly at the factory(and temp jobs in construction)
Contracts given to suppliers creating more jobs in supply chain
Extra spending by workers at Toyota and supply chain will create more jobs in local,national economy
gov will receive extra tax revenues from both the businesses,direct from workers and from spending allowing them to increase their spending e.g. on health creating more jobs
So,initial spending is multiplied creating more spending/jobs.