Answer:
The answer is 69
Step-by-step explanation:
You have to substitute y by 9 and by 3
Since y is equal to 9 and z is equal to 3, we do 10 x 9 - 7 x 3. 10 times 9 is 90, and 7 times 3 is 21.
Then, we do 90-21. 90-21=69. Therefore, 10y-7z = 69.
