Question

Tamara bought yarn for $39 and 2 pairs of knitting needles. Her total cost for the yarn and knitting needles was $69. Tamara writes an equation that represents the cost of each pair of knitting needles. If k represents the cost of each pair of knitting needles, which statements about verifying the value of k are true? Check all that apply.
Tamara should substitute mr022-1.jpg into the equation mr022-2.jpg.
After she substitutes the correct value for k into the equation, Tamara should find that the left side of the equation is equal to the right side.
Tamara should substitute mr022-3.jpg into the equation mr022-4.jpg.
After she substitutes the correct value for k into the equation, Tamara should find that the left side of the equation is not equal to the right side.
To verify the solution to the equation, Tamara multiplies the solution by 2 and then adds it to 39. Then, she checks that it is equal to 69.
To verify the solution to the equation, Tamara adds the solution to 2 and then adds it to 69. Then, she checks that it is equal to 39.

Answer 1

Step-by-step explanation:

Given  

Tamara bought yarn for $39 and 2 pairs of knitting needles. Her total cost for the yarn and knitting needles was $69. Tamara writes an equation that represents the cost of each pair of knitting needles. If k represents the cost of each pair of knitting needles, which statements about verifying the value of k are true? Check all that apply.

We need to write the equation and verify.  So  k represents the cost of each pair of knitting needles

So 39 + 2k = 69

     2k = 69 – 39

     2k = 30

Or k = 30/2

   k = 15

So 39 + 2k = 69

    39 + 2(15) = 69

    39 + 30 = 69

         69 = 69

Answer 2

k = $15

Step-by-step explanation:

The total cost for the yarn and the knitting needles was $69 and Tamara bought yarn for $39.

If each pair of knitting needles cost $k, then we can find the value of k from the above conditions, from the equation

39 + 2k = 69 ......... (1)

⇒ 2k = 30

⇒ k = $15.

Now, after substituting the value of k i.e. $15 in the equation (1) we will get 39 + 2 × 15 = 69

⇒ 69 = 69. (Answer)