Let ‘s’ be the son’s age 12 years ago.
Let ‘f’ be the father’s current age.
4 years ago, the son was:
s-4
So, his father is currently:
3(s-4)
=
3s-12
Therefore:
f = 3s-12
In twelve years, the son will be:
s+12
And the father will be:
f+12
This can also be written as:
3s-12+12 as the fathers younger age would be f = 3s+12
=
3s
So, we know that s+12 is half the fathers current age, meaning the father is currently 2(s+12) which is equivalent to 2s+24. Also, we know that the father is currently 3 times the sons age 12 years ago, so 3s (proven by the calculations we made above). Therefore, 2s+24=3s which means 24=s. We can then substitute this, and we will receive 24+12 = 36
Son’s current age: 36
We then substitute the son’s age 12 years ago into 2s+24 to give us the father’s age.
2(24)+24 = 72
Father’s current age: 72
The measure of each exterior angle is 60° and the polygon has 6 sides ⇒ 4th answer
Step-by-step explanation:
In a regular n-side polygon:
- All sides are equal in lengths
- All angles are equal in measure
- The measure of each interior angle =

- The measure of each exterior angle =

- The sum of interior angle and exterior angle at a vertex is 180°
∵ The measure of an interior angle of a regular polygon is 120°
∵ The sum of interior angle and exterior angle at a vertex = 180°
∴ The measure of each exterior angle = 180 - 120
∴ The measure of each exterior angle = 60°
∵ The measure of each exterior angle = 
- Substitute the measure of the exterior angle by 60
∴ 
- By using cross multiplication
∴ 60 n = 360
- Divide both sides by 60
∴ n = 6
∴ The polygon has 6 sides
The measure of each exterior angle is 60° and the polygon has 6 sides
Learn more:
You can learn more about polygons in brainly.com/question/6281564
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Answer:
<em>The shaded region has an area of 1400 square units</em>
Step-by-step explanation:
<u>Area of Compound Shapes</u>
We are given a shape and it's required to calculate its area. The shape can be divided into three rectangles as shown in the figure attached below.
The lengths of these rectangles are x, y, and z.
The value of x can be calculated as:
x = 60 - 15 - 10 = 35
Similarly:
y = 60 - 15 = 45
z = y = 45
The first rectangle has dimensions of x by 10, thus its area is:
A1 = 35*10 = 350
The second rectangle has dimensions of 60 by 10:
A2 = 60*10 = 600
The third rectangle has dimensions y by 10:
A3 = 55*10 = 450
The shaded area is:
A = 350 + 600 + 450 = 1400
The shaded region has an area of 1400 square units