Answer:
x=13
Step-by-step explanation:
18-5=13. You have to subtract 5 from 5 itself and then 18.
Y = 2x - 5
3x + 8y + 32 = 56
3x + 8(2x - 5) + 32 = 56
3x + 8(2x) - 8(5) + 32 = 56
3x + 16x - 40 + 32 = 56
19x - 8 = 56
<u> + 8 + 8</u>
<u>19x</u> = <u>64</u>
19 19
x = 3.4
y = 2(3.4) - 5
y = 6.8 - 5
y = 1.8
(x, y) = (3.4, 1.8)
Then mark it down by less then 1%, of by whatever the number would be.
Recall the Maclaurin expansion for cos(x), valid for all real x :

Then replacing x with √5 x (I'm assuming you mean √5 times x, and not √(5x)) gives

The first 3 terms of the series are

and the general n-th term is as shown in the series.
In case you did mean cos(√(5x)), we would instead end up with

which amounts to replacing the x with √x in the expansion of cos(√5 x) :
