Answer:
80.
Step-by-step explanation:
When multiplying if the tenth place is " 7" then we look " next door" which is the ones and 8 is great then 5 so we count to from 8 to see when the next number ending in 0 would be in this case its 80. ( if the number is 4 or less count backwards to a number ending with 0 which in that case would have been 70 ) but the answer is 80.
Manipulate the first equation to
y = 22-7z
Then substitute in the second to find z
8(22-7z) + 7z = 127
176-56z+7z = 127
-49z = -49
z = 1
So y = 22-7(1) = 22-7 = 15
y = 15; z = 1
The first equation equals 13
The second one equals 12
to help you discover the answer better I really think the second one