Answer:

Step-by-step explanation:
To write the equation of a line, find the slope between two points. Substitute two points into the slope formula. If the equation has an x-intercept of 6 then the line passes through the point (6,0). Use (6,0) and (4,4) in the formula.

Since m = -2, substitute its value and the point (6,0) into the point slope form. Then simplify.

Answer:
a). 59.049°C
b). 2.1179 seconds
Step-by-step explanation:
Expression representing the final temperature after decrease in temperature of the metal from 100°C to T°C is,
T = 
where x = duration of cooling
a). Temperature when x = 5 seconds
T = 100(0.9)⁵
= 59.049
≈ 59.049°C
b). If the temperature of the metal decreases from 100°C to 80°C
Which means for T = 80°C we have to calculate the duration of cooling 'x' seconds
80 = 
0.8 = 
By taking log on both the sides
log(0.8) =log[
]
-0.09691 = x[log(0.9)]
-0.09691 = -0.045757x
x = 
x = 2.1179
x ≈ 2.1179 seconds
It is 30000 i think dang it