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2 years ago

Length of a rectangle is 7 less than 3 times it’s width. Area is 40cm^2. Find dimensions URGENT

1 answer:

7 0

X= width
length= 3x-7
Area: (x)(3x-7)=40
= 3x^2-7x=40
= 3x^2-7x-40=0
Factorise the equation: (3x+8)(x-5)=0
x=-8/3 (reject because width cannot be negative) or x=5
so width is 5cm and length is 3(5)-7= 8cm !

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The rule for Function A is y= -2/3x

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Answer:

Both functions have negative rates of change

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Step-by-step explanation:

we know that

Function A

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This is the equation of a proportional relationship (the line passes through the origin)

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we have

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substitute

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Verify each statement

Option 1) Both functions have negative rates of change

The statement is true

Because, the rate of change is the slope of the linear equation

Function A ----> $m=-\frac{2}{3}$

Function B ----> $m=-1$

Option 2) Both functions have the same rate of change.

The statement is false (see the explanation)

The rate of change are different ( m=-2/3 and m=-1)

Option 3) When graphed, Function A and Function B are parallel

The statement is false

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Option 4) Function B has a greater rate of change than Function A

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1 > 2/3

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3 years ago

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An echo number has a perfect square if its square root is also a natural number. After some iterations we found that echo number 20222022202220222022 is a perfect square:

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