Casio fx-CG10 Advanced Operation Manual page 50

Sample Solution—Douglas Fir Trees (continued)
Equation:
The power regression equation is y
circumference and y represents the height of Douglas fir trees. To predict the
circumference of trees 3, 45, and 150 meters tall, we evaluated x when y is
equal to these values.
3 18.3670x
45 18.3670x
150 18.3670x
Now, divide each of these equations by 18.3670.
0.7823
0.1633 x
0.7823
2.4500 x
0.7823
8.1668 x
Then, raise each side to the power that is the reciprocal of 0.7823.
0.0987 x
3.1439 x
14.6508 x
Fostering Advanced Algebraic Thinking with Casio Technology
0.7823
0.7823
0.7823
0.7823
18.3670x , where x represents the