The amount a tree grows in one month is directly proportional to the amount of water it is given. When a tree is giving 21 gallons of water it grows 8 cm that month. What is the constant of proportionality for this variation? record your answer to the nearest thousand.

k = 0.381cm/gallon

Step-by-step explanation:

Let the amount a tree grows in one month be x

Let amount of water it is given be y

If the amount a tree grows in one month is directly proportional to the amount of water it is given, then;

x ∝ y

x = ky

k is the constant of proportionality

k = x/y

Given

x = 8cm

y = 21 gallons

k = 8/21

k = 0.381cm/gallon

the sum of all the angles in a triangle are equal to 180

so you can add   the 3 given angles together to equal 180:

5y + 2y + 2y = 180

or since all three angles have the same letter, combine the 3 angles to equal 180:

9y = 180

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