Two equations are shown:

Equation A
y = −5x − 3

Equation B
y = 4x + 5

Which statement best compares the graphs of the two equations?

Both are nonlinear.
Both are linear.
Equation A is nonlinear and equation B is linear.
Equation A is linear and equation B is a nonlinear.

Both are linear.

Step-by-step explanation:

I graphed both of the equations on the graph below to show you that both of them are linear.

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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