Which of these shows the result of using the first equation to substitute for y in the second equation, then combining like terms?
y = 3x
3x + 2y = 18
A. 6x = 18
B. 3y = 18
C. 3x = 18
D. 9x = 18
Answer please

What is the volume of a rectangular prism that is 120 centimeters by 2 meters by 1.5 meters in cubic meters?

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