6.974 rounded to the nearest tenth is 7.0, because 7 is more than 5, and since 9's there, we make that 6 to a 7.
D.36 60 .... because 6 times 6 is 36 and 6 times 10 is 60
Step 1: Read and understand the problem statement.
You are given (time, depth) pairs of (20 s, 8 cm) and (40 s, 0 cm) and asked to write an equation that describes the relationship of depth (y) to time (x).
The rate of change is (0 cm -8 cm)/(40 s -20 s) = -8 cm/(20 s) = -2/5 cm/s. Then in point-slope form using the second point, the linear function rule is
y = (-2/5)(x -40) +0
You can expand this to
y = (-2/5)x +16
y = -0.4x +16 . . . . . . using a decimal number for the slope
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If the bathtubs in your "draining race" start with the same level, the one with the steepest slope (-0.5 cm/s) will win.
The expression (n+3) represents the measure of an exterior angle of a regular octadecagonal.