Mr. O'Donnell goes to the store to buy a shirt. The shirt is $20, but he also has to pay a 9% tax. What is the total price he has to pay?

The total price that he has to pay is $21.8.

Step-by-step explanation:

Mr. O'Donnell goes to the store to buy a shirt. The shirt is $20, but he also has to pay a 9% tax.

First you convert the sales tax percentage to its decimal form: in this case 9% becomes 0.09.

To calculate the cost of the tax, the following multiplication must be performed:

cost of product or service* sales tax (in decimal form) = total sales tax

In this case:

$20*0.09= $1.8

Finally, you must add the value of the total sales tax to the cost of the product or service to obtain the total cost. In this case:

$20 + $1.8= $21.8

So, the total price that he has to pay is $21.8.

y < -3

step-by-step explanation:

-3y - 2 > 7

-3y -2 + 2 > 7+2

-3y > 9

-3y/-3 < 9/-3   (change the inequality sign when multiplying or dividing by a negative number)

y < -3