Using substitution:
first you have to express one variable in terms of the other, in this we can express y in terms of x:
Since both expressions are equal to y, you have to equal both expressions like this:
Now you can solve the equation:
Knowing x=10, you can use any of the expressions we found before to find y. In this case I'm going to use y= -x+9 because it's simpler but boy should give you the same result
So, the answer is x=10 and y=-1
For number 1a. the answer is 7 to 26 or
7:26 or
For number 2a. the answer is 8 to 28 or
8:28 or
For number 3a. the answer is 12 to 13 or
12:13 or
For number 4a. the answer is 19 to 12 or
19:12 or
For number 5a. the answer is 29 to 10 or
29:10 or
For number 6a. the answer is 11 to 28 or
11:28 or
I just did your homework
First you need to make a multiplier:
1-(12/100) = 0.78
Then you multiply the price by 1.12 to get the final answer;
22 * 0.78 = 17.16
This means it cost $17.16 after the 12% sales tax.
Hope this helps! :)