Final answer:
The correct expression for a football team receiving a 5-yard and then a 10-yard penalty is 'D. 5 + 10 yards', which involves simple addition of the two penalties to find the total yardage lost.
Step-by-step explanation:
The expression that best describes a football team receiving a 5-yard penalty and then a 10-yard penalty is D. 5 + 10 yards. This is because each penalty's yards should be added to find the total yardage of the penalties combined..
Now, we know that a yard is a unit of length and today it has a standard definition marked on every football field. Historically, a yard was defined as the distance from the king's nose to the end of his outstretched hand, which could vary with each new king. Thankfully, that's no longer the case, and the standard yard is used consistently in football and other measurements.
An American football field, excluding the end zones, measures 100 yards in length. To convert yards to meters, as you might need in some math problems, remember that 1 meter is approximately equal to 1.094 yards, or to use the standard conversion in feet, 1 yard equals 3 feet, which means 1 meter equals approximately 3.281 feet.