Consider the arithmetic sequence 2, a − b, a + b, −35, … Find a and b. Homework Help ✎
Since this sequence is arithmetic, what has to be true about the differences between terms?
How many times would you add the difference to get from 2 to 35?
2 + d + d + d = 35
d = 11
Since you know the first term and the common difference, you can write all four terms of the sequence.
Use the sequence to write a system of equations: a − b = ? and a + b = ?
a = 18.5, b = 5.5