Its in the tens place so the unit value is 30
The mistake is in step 3:
I: −2m =−12 − 2n
II: 2m = 8 + 8n
the student set both right sides of the equations equal (−12 − 2n = 8 + 8n), but the left sides aren't equal: first equation has -2m, second has +2m so the signs of one of the equations must be inverted first
Please upload the figure too
Any arithmetic sequence can be expressed as:
a(n)=a+d(n-1), a=initial term, d=common difference, n=term number
In this case a=5, and d=-2 so
a(n)=5-2(n-1) which can be simplified...
a(n)=5-2n+2
a(n)=7-2n
The domain is restricted to integers from 1 to +oo.
There is a pattern of -2, -6, so the next number is 20.
