Question

A scientist created a scatter plot to represent the heights of four plants over time. Then, she found a line of best-fit to model the height in centimeters of each plant after x days. The equations of each trend line are given in the table.

Trend Line Equations
Plant
Equation of trend line
1
y = three-halves x + three-halves
2
y = 2 x + 1
3
y = one-half x + 3
4
y = three-halves x + 1

According to the trend line equations, which plants are growing at the same rate per day?
1 and 2
1 and 4
2 and 3
2 and 4

Answer 1

Answer: 1 and 4

Reason:

Both have the same slope of 3/2, aka "three-halves".

The slope is the rate of change. It tells us how fast or slow a plant is growing. The larger the number, the faster the growth.

Recall that y = mx+b has,

m = slope

b = y intercept

Therefore, the slope is thee number just to the left of x.

Answer 2

the answer is one and four