Sorry about my handwriting...
And I couldn't see thing whole thing...
Answer and explanation:
To find : Calculate to the nearest 1/10th meter the length of the side of a 7th, 12th, and 30th hectare square plot.
Solution :
The area of the square is given by,
where s is the side length.
We know, 
1) The area of square plot is 7 hectare.
Area in meter square is 
Substitute the value in the formula,
Side nearest to 1/10th meter is 264.8 meter.
2) The area of square plot is 12 hectare.
Area in meter square is 
Substitute the value in the formula,
Side nearest to 1/10th meter is 346.4 meter.
3) The area of square plot is 30 hectare.
Area in meter square is 
Substitute the value in the formula,
Side nearest to 1/10th meter is 547.7 meter.
Perimeter is 10 units while the area is 8 units I believe but that’s just by counting the boxes
This is a 45-45-90 triangle or a right triangle created by the sides.
Because of this being a right triangle and 45 degrees being given already for one angle you would add 90 and 45 which will give you 135. You would subtract 135 from 180 because all the angles of a triangle add up to 180°. 180-135=45. X=45°