Answer:
21°
Step-by-step explanation:
the angles of triangle abc has to = 180 so subtract the known angles to get 21
angles bca and daf have to be the same so its 21
-7.5 / -2.5 = 3
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You need to go from slope-intercept (

) to standard form (

).
slope-intercept form of your provided values:
now, solve for x and y
Your answer is 
.
Answer: x axis is time in hours, y axis is water level in centimeters
I can't see the rest of the problem since you didnt show it
Step-by-step explanation:
The square root of 81 is 9