Question

Lorena calculated the slope of the linear function that is represented by the table of values as shown. x y –10 15 –8 27 –6 39 –4 51 –2 63 m = StartFraction y 2 minus y 1 Over x 2 minus x 1 EndFraction = StartFraction 63 minus 51 Over negative 2 minus (negative 4) EndFraction = StartFraction 12 Over negative 6 EndFraction = negative 2. What did she do wrong? She used the wrong formula for slope. She used the wrong points to determine the slope. She made a mistake when she subtracted x 1 from x 2. She made a mistake when she subtracted y 1 from y 2.

Answer 1

she made a mistake when she subtracted y1 from y2

Explanation:

Answer 2

She made a mistake when she subtracted x1 from x2.

Explanation:

Step 1 :

a)

The formula used by Lorena to calculate the slope between 2 points is correct

So the statement given in option 1 is not the reason for her mistake

Step 2:

b)

She has taken the fourth and fifth point and correctly used the x and y co ordinates to calculate the slope

Hence the statement in second option is not true

Step 3:

c)

While calculating the slope the denominator is -2 - (-4) . This gives 2 as the answer. But she has made a mistake in this subtraction giving -6 as the answer.

Hence she has made a mistake in subtracting x1 from x2 and this statement is true

Step 4:

d)

She has not made any mistake in subtracting y1 from y2. Hence this statement is not true