Question

In a study using 50 foreign-language vocabulary words, the learning rate L (in words per minute) was found to depend on the number of words already learned, x, according to the equation L(x) = 20 – 0.4x

Answer 1

Here is the complete question

1. State coordinates of x axis

2. State coordinates of y axis

3. State the slope

4. Graph the function

5. Is learning rate increasing or decreasing?

Answer:

1. (50,0)

2. (0,20)

3. Slope = -0.4

4. Check attachment for graph

5. Learning rate is decreasing

Step-by-step explanation:

1.

L(x) = 20-0.4x

20 = 0.4x

x = 20/0.4

x = 50

(50,0)

2

For y coordinate;

L(0) = 20-0.4(0)

= 20

(0,20)

3.

Slope,

Y = -0.4x+20

We compare with

Y = mx+c

m = -0.4

Intercept c = 20

4. Check attachment

5. The slope is negative at m = -0.4 therefore the rate of learning is on a decline. As number of words learnt increases, learning rate falls.