Easy,
the Pythagorean theorem is:

The a and b, being a value that you HAVE
and
c, being the value you are trying to find.
Example: have 1,2 for a triangle what is the third side?

1+4=

5=

Then, just square root to find c.

=c
2.2≈c
5 t'shirts is the minimum she can sell to reach her goal.
Answer:
see below
Step-by-step explanation:
A graphing calculator does this very nicely.
___
If I were graphing by hand, I might divide by 4 and add 7 to get ...
y = 3x +7
Now, you know the slope is 3 and the y-intercept is 7. Another point can be found by going left 1 and down 3 from the y-intercept, or left 2 and down 6 as shown on the attached graph. The line can be drawn through those points.
The <em><u>correct answer</u></em> is:
(10n)² − (1)²
Explanation:
If we evaluate this expression, we square everything in the first set of parentheses; this means we have 10²n² - 1², or 100n² - 1.
This is the expression we were trying to equal.