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4 years ago

Sarah's age is five less than twice her sister's age. Sarah is fifteen years old.

Mathematics

2 answers:

natka813 [3]4 years ago

8 0

The first one would be correct

saul85 [17]4 years ago

3 0

Let her sisters age be x.
=>sister .....x

Sarah.
twice x=2x. then less than 5
=> (2x-5 )
if Sarah = 15 years
by substation, 2x-5=15

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Leona [35]

Answer:

a.the goodness of fit for the estimated multiple regression equation increases.

Step-by-step explanation:

As the value of the multiple coefficient of determination increases,

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3 years ago

Jean throws a ball with an initial velocity of 64 feet per second from a height of 3 feet. Write an equation and answer the ques

Korvikt [17]

Answer:

Step-by-step explanation:

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$s(t)=-16t^2+64t+3$ . That's a.

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Now factor out the -16 since the leading coefficient HAS to be a positive 1:

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Now take half the linear term (half of 4t which is 2), square it (4) and add it into the parenthesis:

$-16(t^2-4t+4)=-3$

BUT since you added in a 4*-16 on the left you have to add it in on the right:

$-16t^2(t^2-4t+4)=-3-64$

which simplifies to

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So the quadratic starts a tiny tiny bit to the left of the origin, but for all intents and purposes we can say it starts at the origin (x = 0) and ends at

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3 years ago

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Jobisdone [24]

Answer:

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