Answer:

Step-by-step explanation:
Let
x -----> the number of minutes
y ----> the balloon's height in feet
we know that
The linear equation in slope intercept form is equal to

where
m is the slope
b is the y-coordinate of the y-intercept
In this problem we have that
The slope is equal to
----> is negative because is a decreasing function

Remember that the y-intercept is the value of y when the value of x is equal to zero
In this context the y-intercept is the height of the balloon when the time is equal to zero (initial height)
substitute

-3x from both sides so it looks like 2x=20 and divide by 2 and x=10
4¹ = 4
4² = 16
4³ = 64
4⁴ = 256
(4⁵ = 1,024)
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