T-shirts are on sale for $4 off he regular price. Jeb buys 5 T-shirts for a total of 45.05, including a 6% sales tax. Which equation can Jeb use to find the regular price, r, of 1 T-shirt?

1.06 * 5 (r-4) = 45.05

Step-by-step explanation:

Let r represents the regular price of each T-shirt,

After getting $ 4 off in regular price,

New price of each T-shirt = r - 4,

Thus, new price of 5 T-shirts = 5 * price of each T-shirt

= 5 (r - 4)

Since, there is 6% sales tax,

Then, the final price after discount = 5 (r - 4) + 6% of (5 (r-4))

= 5 (r-4) + 0.06 (5 (r-4))

= 1.06 * 5 (r-4)

According to the question,

1.06 * 5 (r-4) = 45.05

Which is the required equation.