Gianna is substituting t = 2 and t = 7 to determine if the two expressions are equivalent.

5 (2 t + 3) 5 t + 25

Both expressions are equivalent to 35 when t=2

Step-by-step explanation:

Let's start by substituting with t=7.

Expression 1:

5 (2t+3) If we substitute t for 7 we get:

5 (2 (7) + 3)

Then we'll multiply inside the parenthesis:

5 (14+3).

Then we will add inside the parenthesis:

5 (17).

Then multiply and you get: 85

Expression 2: Let's apply the same steps we used in expression one and apply it to expression 2

5t+25

5 (7) + 25

35+25

60

Then compare and we get 60≠80 which is NOT correct. Now let's try our last option: Substituting with t=2.

Expression 1:

5 (2t+3)

5 (2 (2) + 3)

5 (4+3)

5 (7)

35

Expression 2:

5t+25

5 (2) + 25

10+25

35

We can then conclude both expressions are equivalent to 35 when t=2