Problem
The next Algebra test is worth 100 points and contains 35 problems. Multiplechoice questions are worth 2 points each and word problems are 7 points each. How many of each type of equation are there?
Solution
Step 1 ：Let x be the number of multiple-choice questions, and y be the number of word problems
Step 2 ：x + y = 35
Step 3 ：2x + 7y = 100
