Ernesto tried to determine the solution for the system of equations using substitution. his work is shown below.
x – y = 7
3x – 2y = 8
step 1: x = y + 7
step 2: 3(y + 7) – 2y = 8
step 3: 3y + 7 – 2y = 8
step 4: y + 7 = 8
step 5: y = 1
in which step did ernesto make the first error?
step 1
step 2
step 3
step 4

picture below

the total estimated nappy use.=10,500,000

step-by-step explanation:

given that on an average the average baby uses 3528 napkins.

in a particular year 2014, the number of births were 299697 in new south wales.

rounding off the number of births to the nearest hundred thousand we have

no of birtsh = 300000

also rounding off the average usage to nearst thousand we get

average use of a baby = 3500

hence total number of nappy estimated to be used = 3500x300000

= 10,500,000

answer is 10,500,000 nappies