If you are good at sequences in math please help I am giving more points

First one

Step-by-step explanation:

a11 = a1 + (11-1)(7)

50 = a1 + 70

a1 = -20

an = -20 + 7(n-1)

-20 + 7(n-1)

Step-by-step explanation:

It's already given that d, or the common difference, is 7. The only thing left to do is to find the first term of this sequence.

We are given that = 50.

If we subtract the common difference 10 times we can find the first term.

- 7 x 10 = -70

50 - 70 = -20

The first term is -20. The only choice that shows this is the first one.

rectangle that is ther answer you

step-by-step explanation:

no not all of them.

step-by-step explanation:

some of them have a square base.