Answer:
1st picture:
2nd Picture:
3rd picture:
Explanation:
For 1st picture:
Given:
Interior angle of a regular polygon = 140°
To find:
no. of side=?
Solution:
The formula for the sum of the interior angles in a polygon is:

- where n is the number of sides in the polygon.
Since we know that the measure of one interior angle is 140°, we can set up the following equation:
sum of interior angle= n*interior angle of a regular polygon
Now, Substituting value in above formula, we get,
140n = 180(n - 2)
opening bracket
140n =180n-360
Solving for n, we get:
180n-140n=360
40n=360
n=360/40
n=9
Therefore, the polygon has 9 sides.

For 2nd Question:
Given:
Hypotenuse = 34 ft
Perpendicular = 16 ft
Base=?
We can use Pythagoras theorem to find the value of base.
so, we have,

substituting value:

solving for base², we get

doing square root on both side,we get

Therefore, Rebecca's yard's wide is 30 feet,

For 3rd question:
(5x-1)°=(3x+11)° Being alternate interior angle
5x-1=3x+11
adding both side by 1.
5x=3x+11+1
5x=3x+12
subtracting both side by 3x.
5x-3x=12
2x=12
dividing both side by 2.

x=6
therefore, the value of x is 6.