Negative 45 or -45 because different signs with multiplication are always negative
8 x 2 = 16
Square root of 16 = 4
One side of the square is 4 meters.
<u>Answer:</u>
BC = 18 cm
<u>Step-by-step explanation:</u>
As we can see from the diagram:
AB + BC + CD = AD
⇒ 10 cm + BC + 11 cm = 39 cm
⇒ BC + 21 cm = 39 cm
⇒ BC = 39 cm - 21 cm
⇒ BC = 18 cm
B would be the correct answer