The sum of three lengths of a fence rages from 31 to 40 inches. Two side lengths are 9 and 12 inches. If the length of the third side is x inches, write and solve a compound inequality to show the possible lengths of the third side
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Answer:
10 ≤ x ≤ 19
Step-by-step explanation
The sum of the three lengths is 9 + 12 +x = 21 + x
We know the sum ranges from 31 to 40
So we get the inequality
31 ≤ 21 + x ≤ 40
Subtracting 21 from each part of this inequality give
31-21 ≤ x ≤40-21
10 ≤ x ≤ 19