2. #1 When 6 is added to four times a number, the result is 50. Find the number and build the algebraic concept. Is it an expression or equation? Use the river method to confirm if your answer is correct or not. Answer: 6 + 4n = 50

3. #2 The sum of a number and 9 is multiplied by -2 and the answer is -8. Build it. Answer: -2(n + 9) = -8

4. #3 On an algebra test, the highest grade was 42 points higher than the lowest grade. The sum of the two grades was 138. Find the lowest grade. Answer: ( h + 42) + l = 138

5. #4 In a given amount of time, Jamie drove twice as far as Victoria. Altogether they drove 90 miles. Find the number of miles driven by each. Answer: R + 2R = 90

6. #5 The first stage of a rocket burns 28 seconds longer than the second stage. If the total burning time for both stages is 152 seconds, how long does each stage burn? Answer: x+x+28=152

7. #6 In a student election, 584 students voted for one or the other of two candidates for president. If the winner received 122 more votes than the loser, how many votes were cast for each candidate? Answer: x+x+122=584