Answer:
a = 4 cm
Step-by-step explanation:
Using Pythagoras' identity in the right triangle.
The square on the hypotenuse is equal to the sum of the squares on the other 2 sides, that is
a² + 3² = 5²
a² + 9 = 25 ( subtract 9 from both sides )
a² = 16 ( take the square root of both sides )
a = = 4
Answer:
a) In the interval of [1980,1983].
b) In the interval of [1991, 1996].
Step-by-step explanation:
Fuel efficiency:
The fuel efficiency, for the cars, in x years after 1980, is given by:
15.9 is the fuel efficiency in 1980.
a. In what years was the average fuel efficiency for cars less than 17 mpg (in interval form)?
From 1980 to:
3.06 = 1980 + 3 = 1983. So
In the interval of [1980,1983].
b. In what years was the average fuel efficiency for cars more than 20 mpg (in interval form)?
From x until 1996.
11.38 = 1980 + 11 = 1991. So
In the interval of [1991, 1996].