Answer:
y = - 4.5x + 120
75 = - 4.5x + 120
x = 10 minutes
Step-by-step explanation:
To model the scenario described above, we use the linear equation model ;
Where ;
y = bx + c ; c = intercept ; b = slope ; y = altitude at time x
The initial altitude of the hot air Ballon here is the intercept = 120 meters
The descent rate = 4.5 m per minute is the slope ; since it is descent, then the slope will be negative as the altitude will reduce.
Hence, we have ;
y = - 4.5x + 120
Hence, the time altitude will be 75 cabnbe modeled as :
y = 75
75 = - 4.5x + 120
75 - 120 = - 4.5x
- 45 = - 4.5x
x = 10 minutes