Answer:Correct B
s + j = 32
s − j = 4
s = seniors
j = juniors
total students signing up is 32 → s + j = 32
four more seniors sign up than juniors → s − 4 = j → s − j = 4
When the system is solved: s + j = 32 and s − j = 4.
When the system s + j = 32, s − j = 4 is solved: s = 18 and j = 14
s + j = 18 + 14 = 32
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