Recall that addition problems like 3478 + 521 can be written and computed using expanded n...

Recall that addition problems like 3478 + 521 can be written and computed using expanded notation as shown here, and answer the questions that follow.

a. Write a corresponding addition algebra problem (use x for 10) and find the answer.

b. Write a subtraction problem and the corresponding algebra problem and find the answer.

c. Write a multiplication problem and the corresponding algebra problem and compute the answer.