Final answer:
Alex received $140 for the lawn tractor.
Step-by-step explanation:
To find out how much money Alex received for the lawn tractor, we need to set up an equation based on the given information. Let's say he received x dollars for the accessories. According to the problem, he received twice that amount for the lawn tractor, so he received 2x dollars for the lawn tractor. The total amount of money received is $210, so we can write the equation as: x + 2x = 210. Simplifying this equation gives us 3x = 210. Dividing both sides of the equation by 3, we get x = 70. Therefore, Alex received $70 for the accessories and $140 for the lawn tractor.