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At age 16, Logan weighed 162 pounds. When he was 20, he weighed 198 pounds. Write a linear equation that relates Logans wait to his age.

User MachineElf
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2 Answers

1 vote
he gained 9 pounds per year I am pretty sure. Hope this helps you!!
User MALON
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Answer:
y = 9x + 18
where y is the weight and x is the age

Step-by-step explanation:
Assume that the age is x and the weight is y.
We are given that:
At age of 16, Logan was 162 pounds. Therefore, point on the line is (16,162)
At age of 20, Logan was 198 pounds. Therefore, point on the line is (20,198)

The general form of the linear equation is:
y = mx + c
where m is the slope and c is the y-intercept

1- getting the slope:
slope (m) = (y2-y1) / (x2-x1)
m = (198-162) / (20-16) = 9
The equation now becomes:
y = 9x + c

2- getting the y-intercept:
The two given points belong to the required line. This means that each of them satisfies the equation of the line.
So, to get the y-intercept, we will substitute with one of the points in the equation and solve for c.
I will use point (16,162) as follows:
y = mx + c
162 = 9(16) + c
162 = 144 + c
c = 162 - 144 = 18
Therefore, the equation becomes:
y = 9x + 18

Hope this helps :)
User Raphiel
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