First notice that the triangle with sides

and the triangle with sides

are similar. This is true because the angle between sides

in the smaller triangle is clearly

, while the angle between sides

in the larger triangle is clearly

. So the triangles are similar with sides

corresponding to

, respectively.
Now both triangles are

, which means there's a convenient ratio between its sides. If the length of the shortest leg is

, then the length of the longer leg is

and the hypotenuse has length

.
Since

is the shortest leg in the larger triangle, it follows that

, so
Addition/Subtraction and. Multiplication/ Division ... So checking one operation with its opposite is a good way to help verify your answer.
Answer:
I would say -19, not 100% sure tho!
Answer:
I am pretty sure it is when you have a sequence of numbers that you are subtracting or adding from by the same constant over and over
Step-by-step explanation:
an=a1+(n-1)d
d=common difference
an= the nth term in the sequence
a1 first term in the sequence. (Usually you can plug in 1, as the n, and work from there)