3. a. What trend line, in slope-intercept form, models the data from the Example 2 Try it?
b. Explain why there could be no data points on a trend line,
yet the line models the data.
EXAMPLE 2 Understand Correlation
How can the relationship between the hours after sunrise, x, and the
temperature, y. be modeled?
The data points on the scatter plot approximate a line. Sketch a trend line
that best fits the data to determine whether a linear function can model the
relationship
Temperature After Sunrise
dy
72
I
68
Temperature (7)
The trend line suggests
that a linear function can
model the relationship
64
60
2 4 6 8 10
Hours After Sunrise

step-by-step explanation:

y = | -2(-2) |     →     y = | 4 |     →     y = 4       ⇒   (-2, 4)

y = | -2(-1) |     →     y = | 2 |     →       y =   2       ⇒   (-1, 2)    

y = | -2(0) |     →     y = | 0 |     →       y = 0         ⇒   (0, 0)

y = | -2(1) |   c →     y = | -2 |     →     y =   2         ⇒   (1, 2)    

y = | -2(2) |     →     y = | - 4 |     →     y =   4         ⇒   (2, 4)  

a

step-by-step explanation:

given the 2 equations

- x + y = - 2 → (1)

2x - 3y = 4 → (2)

multiplying (1) by 2 and adding to (2) will eliminate the x- term

- 2x + 2y = - 4 → (3)

add (2) and (3) term by term

(2x - 2x) + (- 3y + 2y) = (4 - 4), simplifying gives

- y = 0 ⇒ y = 0

substitute y = 0 in either of the 2 equations for corresponding value of x

substituting in (2) gives

2x = 4 ( divide both sides by 2 )

x = 2

solution is (2, 0 ) → a

the answer is  

d.

8 m

hope you got it down chief.