ALgebra problems

19. Simplify.

20. Decide whether the following is written in simplest form.

21. Simplify by combining like terms.

22. Simplify by combining like terms.

23. Find the perimeter of the triangle shown in the figure. Write your answer in reduced radical form.

24. Perform the indicated multiplication. Then simplify.

25. Perform the indicated multiplication. Then simplify the radical expression.

26. Perform the indicated multiplication. Then simplify the radical expression.

27. Perform the indicated division. Rationalize the denominator, if necessary. Then, simplify.

28. Solve.