How can you tell if two points lie along the same grid line just by looking at the ordered pairs?

Aley is at the store buying some supplies for an art project. she decides to buy some colored pencils for $3.95 and a drawing tablet. the total cost of the supplies before sales tax is $6.94. what is the cost of the drawing tablet? $10.89 $2.99 $1.76 $3.01