Amanatee surfaced for air 6 times in 240 seconds. how many seconds went by before the manatee surfaced the fourth time if it held its breath for the same rate?

step-by-step explanation:

if y=4x then you will substitute 4x in for y in the second equation.

8x + 4x = 18 combine like terms

12x = 18 divide by 12 on both sides

x = 18/12 or 3/2

now replace x in the first equation with 3/2 to get

y = 4 3/2

y = 6

the answer is a

(3/2,6)

hope that .

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