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3 years ago

10

The length of rectangular picture is 3 times as long as the width. If the area of the picture is 147 square inches, find the len

gth and width of the picture.

1 answer:

SIZIF [17.4K]3 years ago

8 0

Answer:

l= 21 w=7

Step-by-step explanation:

l=3w

147=(3w)×w

147=3w^2

49=w^2

7=w

so now we have w=7. Plug that in to find l...

l=3w

l=3×7

l=21

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Answer:

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Part b) About 8.3 feet

Part c) The domain is $0 \leq x \leq 48.6\ ft$ and the range is $0 \leq y \leq 8.3\ ft$

Step-by-step explanation:

we have

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This is a vertical parabola open downward (the leading coefficient is negative)

The vertex represent a maximum

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y is the flight of the balls in feet

Part a) How far did the ball fly?

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Remember that

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The formula to solve a quadratic equation of the form

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substitute in the formula

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Part b) How high above the ground did the ball fly?

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Find out the derivative and equate to zero

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Solve for x

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To determine the x-coordinate of the vertex, find out the midpoint between the x-intercepts

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To determine the y-coordinate of the vertex substitute the value of x in the quadratic equation and solve for y

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A reasonable domain is the distance between the two x-intercepts

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All real numbers greater than or equal to 0 feet and less than or equal to 48.6 feet

A reasonable range is all real numbers greater than or equal to zero and less than or equal to the y-coordinate of the vertex

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