1. <span>(b-7)(2b-7) = 2</span>

-21b +49; b = 42 => 2*

-21*42 + 49 =
3528 - 882 + 49 = 2695;
Answer:
Top is 18, Bottom goes 6 for 12, then 7 for 14, then 10 for 20
Step-by-step explanation:
2 guests = 1 table
This question is not elaborate.
7 = 3 does not make sense.
Otherwise, do you mean x = 3?
Please revise your question.
we know that having similar triangles so the ratio of sides,area and volume are same.

we know that
will be the area of triangle.

so 
so the ratio of the perimeter of two triangles will be

ratio of the perimeter=