Answer:
D. 6
Step-by-step explanation:
the similarity theorem:
x/9 = 8/12
12x=8 (9)
12x = 72
x = 72/12
x = 6
Answer:
The above equation has two solution !
x = 0 , x = 1
Step-by-step explanation:
[ Refer to the attachment ]
Here is the equation:

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You need to get "x" by itself so minus 3 from each side

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Divide 8 by 2

÷

x=4
So each 4 is equivalent to 4
Lets check:

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So that means that Marcus practiced the piano for 4 hours and Donnel practiced for 7