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3 years ago

Help me please????????

Mathematics

1 answer:

Novosadov [1.4K]3 years ago

8 0

9514 1404 393

Answer:

A, C, E

Step-by-step explanation:

The proportional relations on the list are ...

feet and inches
flour and bread
gallons and cost

We often model running distance and time as proportional, but a marathon is a long enough run that speed is rarely constant. It usually decreases over the course, and may increase near the end.

A relationship is proportional if there is a constant multiplier that relates the output to the input.

_____

<em>Additional comment</em>

For the relations listed above, the constants are ..

the conversion factor between feet and inches
the amount of flour in a bread recipe
the price of a gallon of gas

For running time and distance, the multiplier is <em>speed</em>. The relation is only proportional if speed is a constant.

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Step-by-step explanation:

Circle P has radius 14 feet.

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We plug in the radius to get:

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Answer:

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Step-by-step explanation:

We must remember that a parabola is represented by a quadratic function, which can be formed by knowing three different points. A quadratic function is standard form is represented by:

$y = a\cdot x^{2}+b\cdot x + c$

Where:

$x$ - Independent variable, dimensionless.

$y$ - Dependent variable, dimensionless.

$a$ , $b$ , $c$ - Coefficients, dimensionless.

If we know that $(3, -30)$ , $(-2, 0)$ and $(18, 0)$ are part of the parabola, the following linear system of equations is formed:

$9\cdot a +3\cdot b + c = -30$

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This system can be solved both by algebraic means (substitution, elimination, equalization, determinant) and by numerical methods. The solution of the linear system is:

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