68,309 one hundred percent sure
Answer:
±6i√2
Step-by-step explanation:
Recall that the square root of a negative number is imaginary, which is shown by the use of "i."
Examples: √4 = ±2; √4 = i√4 = ±i2
Then √72 = ±√36√2 = ±6√2, and
√(-72) = ± i√36√2 = ±6i√2
Note that this is identical to the result shown in the problem: √(36·2·(-1) )
2 separate 7 ft boards = (2 * 7) = 14 feet
1 ft = 12 inches....so 14 feet = (14 * 12) = 168 inches
168/11 = 15.27 <== she has 15 eleven inch boards.