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The equation x power 3 - 6x=72 has a solution between 4 and 5.

The equation x power 3 - 6x=72 has a solution between 4 and 5.-example-1
User Kevin Tan
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2 Answers

3 votes

Answer:

4.6

Explanation:

Y needs to = 72. When x=5, Y = X3 - 6X Y = 53 - 6(5) Y = 125 - 30 = 95 95 > 72 95 is way too high so we try a lower number

When x=4 Y= X3 -6X Y = 43 - 6(4) Y = 64 - 24 Y = 40 40 < 72 40 is way too low so we try a higher number, 4.5

When x=4.5 Y = X3 - 6(4.5) Y = 4.53 - 6(4.5) Y = 64.125 64.125 < 72 64.125 is too low so we try a slightly higher number: 4.6

When x=4.6 Y = X3 - 6(X) Y = 4.63 - 6(4.6) Y = 97.336 - 27.6 Y = 69.736 69.736 < 72 69.736 is too low so we try a slightly higher number

When x=4.7 Y = X3 - 6(X) Y = 4.73 - 6(4.7) Y = 103.823 - 28.2 Y = 75.623 75.623 > 72 75.623 is too high so we should try a number in between 4.6 and 4.7

When x=4.65 Y = X3 - 6(X) Y = 4.653 - 6(4.65) Y = 100.54 - 27.9 Y = 72.64 72.64 > 72 72.64 is too high so to 1 decimal place, the solution to the equation is 4.6.

User Cleary
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4.5k points
3 votes

Answer:

x power 3(x cube)- 6x -72=0 there it has change to quadratic equation x power 3(x cube)-12x+6x-72=0

User Geri
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4.5k points