Let the three gp be a, ar and ar^2
a + ar + ar^2 = 21 => a(1 + r + r^2) = 21 . . . (1)
a^2 + a^2r^2 + a^2r^4 = 189 => a^2(1 + r^2 + r^4) = 189 . . . (2)
squaring (1) gives
a^2(1 + r + r^2)^2 = 441 . . . (3)
(3) ÷ (2) => (1 + r + r^2)^2 / (1 + r^2 + r^4) = 441/189 = 7/3
3(1 + r + r^2)^2 = 7(1 + r^2 + r^4)
3(r^4 + 2r^3 + 3r^2 + 2r + 1) = 7(1 + r^2 + r^4)
3r^4 + 6r^3 + 9r^2 + 6r + 3 = 7 + 7r^2 + 7r^4
4r^4 - 6r^3 - 2r^2 - 6r + 4 = 0
r = 1/2 or r = 2
From (1), a = 21/(1 + r + r^2)
When r = 2:
a = 21/(1 + 2 + 4) = 21/7 = 3
Therefore, the numbers are 3, 6 and 12.
Answer:
Ray KM is an angle bisector of NKL.
Step-by-step explanation:
Step-by-step explanation:
first one is 6:9
second is 20:40
sorry I'm not sure about the others!
Answer:

Step-by-step explanation:
h(x)=-4(x-3)(x-1) Copy the original equation
Factor out the two parentheses
Distribute the -4
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The amount more of rain that fell in those three days than normally falls in July and August combined was 31.19 cm.
<h3>How much more rain fell in those three days?</h3>
The amount of rain in those three days was 41.2 cm.
The combined normal rain July and August is:
= 6.36 + 3.65
= 10.01 cm
The difference is therefore:
= 41.2 - 10.01
= 31.19 cm
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