I need a formula for 1 and 3. Number 2 i just can't figure out.

1. The width of a rectangle is 7 less than twice its length. If the area of the rectangle is 23 cm, what is the length of the diagonal?

Note: Your answer must be a number. It may not contain any arithmetic operations.

The length of the diagonal is _______ cm.

2.Find all possible solutions. Give your answers in increasing order. Give your answers to the nearest thousandth.

The smaller possible solution is ________. Is it a solution? (yes or no)

The larger possible solution is ________. Is it a solution? (yes or no)

3.Expand the expression using the Binomial Theorem:

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