6x-18
you pretty much h just multiply both the first part of the parentheses by the number outside, then the second :)
The equation representing when the two planes would be at the same altitude is 9x=486
<h3>In terms of mathematics, what is an equation?</h3>
Equation: A declaration that two expressions with variables or integers are equal. In essence, equations are questions, and attempts to systematically identify the solutions to these questions have been the driving forces behind the creation of mathematics.
From (a) we get that: Altitude of Plane A = 990-18x
Altitude of Plane B = 1476-27x
make 890 - 18x = 1476-27x
-18x+27 x = 1476-890
9x=486
X= 54
so pass 54 seconds will the two plane at the same altitude.
To learn more about equations from given link
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Answer:
V =648 mm^3
Step-by-step explanation:
The volume of a prism is given by
V = l*w*h
V = 6*9* 12
V =648 mm^3
= -1/9 im pretty sure is the answer
Noelia has 216 cards after buying part of the set with her friends.
<h3>What is addition?</h3>
Combining items and counting them as a single, large group is done through addition.
Given that, Noelia has 144 role-playing cards.
Now, she bought 72 cards more, therefore, the number of cards Noelia has is:
144 + 72
= 216
Hence, Noelia has 216 cards after buying part of the set with her friends.
Learn more about the addition:
brainly.com/question/29560851
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