Question

Help please

State whether the graph of the linear relationship is a solid line or a set of unconnected points. Complete the explanation of your reasoning.

The relationship between the number of $3 lunches you buy with a $150 school lunch card and the money remaining on the card

The relationship is a ( set of unconnected points, solid line )
because you (can, cannot) buy a ( positive number of lunches, fractional part of a lunch)

Answer 1

The relationship is a solid line because you can buy a positive number of lunches.

Explanation:

$3 lunches $150 school lunch card

Let number of lunches = x

Let number of amount remaining on card = y

y = 150 - 3x

When you buy 1 lunch

y = 150 - 3(1)

150 - 3

y = 147

When you buy 2 lunches

y = 150 - 3(2)

150 - 6

y = 144

The decrease in the amount is constant and you can see on the graph that it is linear.