From the given information, a exists jointly proportional to b and c.
then 
Therefore, the value of a exists 2.
<h3>
What is the value of a?</h3>
Given, a exists jointly proportional to b and c.

Taking K as the constant of proportionality.
a = K b c
For b = 8 and c = 9, the value of a = 4
4 = K(8)(9)
4 = 72 K
Dividing the equation by 72, we get

Using the value of K in the equation:

Substitute the values of b = 2 and c = 18, in the above equation

a = 2
Therefore, the value of a exists 2.
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Answer: See explanation. Hope this helps, please consider making me Brainliest.
Step-by-step explanation:
To find the rate of change, subtract then divide. This is especially a good strategy when you have the x and y values when x = 0:
604 - 460 = 144
144 divided by 18 =
8
Therefore, the rate of change is 8. We can even go further to create an equation for this:
y intercept = 460 (because 0 multiplied by the rate of change would be 0).
slope = 8
Slope-intercept form: y = mx + b --> y = 8x + 460
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Answer:

Step-by-step explanation:
<em>Nothing can be done with the equation because there is no quotient. </em>
If there was, would be able to solve for x.
La formula para calcular cualquier descuento esta dada por (100 - descuento)/100
en ese caso seria Y = (1-0.3)X = 0.7X