The country population would be 827 million in about 20 years.
This can be found by replacing "t" with 20 and solving. The solution would be about 8273.28 million. Thus meaning in about 20 years, the population would be 827 million.
The graph will cross at the coordinates (-2, 9)
<h3>How to solve equations?</h3>
y = 3x + 15
y = 3 - 3x
y = 3x + 15
Hence,
when x = 2
y = 3(2) + 15 = 21
when x = 0
y = 3(0) + 15 = 15
y = 3 - 3x
when x = 2
y = 3 - 3(2)
y = 3 - 6
y = -3
when x = 0
y = 3 - 3(0)
y = 3
Therefore, let's check if the equation will cross.
y = 3x + 15
y = 3 - 3x
using substitution,
3 - 3x = 3x + 15
3 - 15 = 3x + 3x
- 12 = 6x
x = -12 / 6
x = -2
y = 3 - 3(-2)
y = 3 + 6
y = 9
Therefore, the graph will cross at the coordinates (-2, 9)
learn more on equations here: brainly.com/question/19297665
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Answer:
14 hours
Step-by-step explanation:
Let's call the task 3x
The older bro does twice as younger so it would be 2x long and younger brother work x long
Since the totsl of work is 3x = 21 x woul be 21÷3 = 7
the older brother must work 2 × 7 = 14 hours long
