Answer:
a1 = 2
d = 3
an = 2 + (n - 1) * 3
a7 = 20
a59 = 176
Steps:
a1 is the initial value (when n equals 1), and since there are 2 crosses, it is 2.
d is the added value to each amount of crosses. And since the second amount is 5 and the third amount is 8, we can determine that each n is adding 3 crosses, therefore making d = 3.
The equation is simply plugging in the values for a1 and d.
A7 is simply plugging in 7 for n in the equation and solving for it. So;
a7 = 2 + (7 - 1) * 3
a7 = 2 + 6 * 3
a7 = 2 + 18
a7 = 20
And same thing as the last for 59 except substitute 59 in for where you put 7;
a59 = 2 + (59 - 1) * 3
a59 = 2 + 58 * 3
a59 = 2 + 174
a59 = 176
I think you've got it, I don't know man.
First isolate the power of 10 on the right side by dividing both sides by 5:
Now you're free to take the logarithm and simplify where you can:
Then solve for 
:
Answer:
12.62
Step-by-step explanation:
imagine a circle with the center at the corner (let's call it A) with the 31 degree angle. the radius is AB.
so,
x = sin(31)×AB
and
21 = cos(31)×AB
therefore,
AB = 21/cos(31) = 24.4993...
=> x = sin(31)×24.4993... = 12.62 (12.61807...)
