Question

Problem

A knitting pattern for a shawl calls for 8

stitches in the first row. Each row after that

has 2 more stitches than the previous row.

The explicit rule ax = 8 + (k − 1)2 gives the

number of stitches in the nth row row.

Answer 1

1st question: C

2nd : 8

3rd : 46

4th : 540

Answer 2

The n row has
`2n+6` stitches.

Explanation:

The given expression is

`a_(k)=8+(k-1)2`

Where
`d=2` and
`a_(1)=8`.

The number of stitches in the n row are expressed as

`a_(n) =8+2n-2\\a_(n) =2n+6`

Therefore, the n row has
`2n+6` stitches.

Notice that the result is an expression, that is beacuse the problem is asking for a general solution, it's asking for the n row, which refers to certain row in general terms.