Sagot :
JOINT VARIATION
Direction: The variable A varies jointly with b and the square of c, and A = 9 when b and c are both 3. Find c when A = 48 and b = 4.
Answer:
[tex]\Large \blue{\bold{c = 36.000000004}}[/tex]
Step-by-step explanation:
Step 1: Write the correct equation. Joint variation problems are solved using the equation z=kxy if z varies jointly as x and y.
[tex]\large \bold{A = kbc^{2}}[/tex]
Step 2: Use the information given in the problem to find the value of k. In this case, you need to find k if A = 9 when b and c are both 3.
[tex]A = kbc² \\ 9 = k(3)(3²) \\ 9=27k \\ \frac{9}{27} = \frac{ \cancel{27}k}{ \cancel{27}} \\ \bold{\frac{1}{3} = k}[/tex]
Therefore, the constant of variation k is ⅓.
Step 3: Rewrite the equation from step 1 substituting in the value of k found in step 2.
[tex]\large \bold{A = bc²}[/tex]
Step 4: Use the equation found in step 3 and the remaining information given in the problem to answer; in this case, you need to find c when A = 48 and b = 4
[tex]A = \frac{1}{3}bc² \\ 48 = (\frac{1}{3})(4)c² \\ 48=1.3333333332c² \\ \frac{48}{1.3333333332} = \frac{\cancel{1.3333333332}c²}{\cancel{1.3333333332}} \\ \bold{36.000000004 = c²}[/tex]
Thus, the value of c is equal to 36.000000004.
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- brainly.ph/question/13349590
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