Step-by-step explanation:
Here is a helpful method I taught my students in my mini lesson...
For you to remember, 22= 4, and 32= 9. Hence the answer to the root of 8 lies between the numbers 2 and 3. However, since the square of 3 equals to 9 which is larger than 8, the root 8 value lies in between the number 2.8 and 2.9.
Not sure why such an old question is showing up on my feed...
Anyway, let

and

. Then we want to find the exact value of

.
Use the angle difference identity:

and right away we find

. By the Pythagorean theorem, we also find

. (Actually, this could potentially be negative, but let's assume all angles are in the first quadrant for convenience.)
Meanwhile, if

, then (by Pythagorean theorem)

, so

. And from this,

.
So,
The translation of the sum a and n is a+n
(2x-y = -3 × y = 0 × (0, 0) × ( -1, 1) × (1, -1) =
(2x - y = -3 × y =0 × (0)) ×, × 0 ×, × 1 ×, × -1
The answer is 7/10 because the even values are 2,4,6, and the others are 7,8,9,10. Added together, it adds up to 7/10