Answer:
x = 7
Step-by-step explanation:
the 2 is doubled so the 3.5 has to be doubled as well
From the given figure

Since XY = 5.1 and XZ = 7.7, then

To find x, use the inverse of cos

Use the calculator to find x

The answer is
Let
denote the number of seats in the
-th row.
is arithmetic, so

for some constant
.
We're told
and
, so that



and so on up to

The pattern continues:


and so on up to

Answer: 4
Step-by-step explanation: yup