Answer:
Associative property of addition
Step-by-step explanation:
To “associate” means to connect or join with something. According to the associative property of addition, the sum of three or more numbers remains the same regardless of how the numbers are grouped.
Answer:
It will take 4 minutes and 30 seconds for hot coffee to cool to a temperature of 25 ° C
Step-by-step explanation:
This problem can be modeled by a first order equation
T(t) = TA + kt
In which TA is the temperature at instant zero and r is the rate of warming(g>0) or cooling(k<0). t is the time in minutes.
The initial temperature of the cup of coffee is 70ºC. So TA = 70. The temperature cools at the rate of 10ºC per minute, so k = -10. So, the equation of the model is:
T(t) = 70 - 10t
We want to know the instant of time when T = 25, so:
25 = 70 - 10t
10t = 70 - 25
10t = 45
t = 4.5 minutes
It will take 4 minutes and 30 seconds for hot coffee to cool to a temperature of 25 ° C
As BD is perpendicular....given
ADB AND CDB are 90° ......as BD is perpendicular so 90°
BD= BD .....common line !
Eh that ones hard you sure thats all the ansers