Renee wants to solve the system of equations. Which number can she multiply the first equation by so that when the two equations are added together, the y term is eliminated? Two-thirds x + one-fifth y = 6 One-sixth x minus 3 y = 8 –15 –5 5 15

15

Step-by-step explanation:

The given equations are as follows:

The coefficient of y in the second equation is -3.

So in order to eliminate y we need to multiply the first equation by a value so that the coefficient of y becomes 3.

Since the coefficient of y in the first equation is \[\frac{1}{5}\], it needs to be multiplied by 15.

So the required multiplier for the first equation is 15

i'm assuming that it's c.)   volcanoes built the mountains and earthquakes tore them down.

ending amount = beginning amount / (2^n)

where "n" = number of half-lives (or elapsed time / half-life)

ending amount = 50 mg / (2 ^10 / 5.3)

ending amount = 50 mg / (2 ^ 1.8867924528)

ending amount = 50 m / 3.6981210597

ending amount = 13.5203794557 mg

or about 13.5 mg remain

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