SOLUTION: what is the equation for; 3 times the difference of the square of a number and 1 is 72

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Question 570457: what is the equation for; 3 times the difference of the square of a number and 1 is 72
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
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what is the equation for; 3 times the difference of the square of a number and 1 is 72
:
Write what it says
3(x^2-1) = 72
3x^2 - 3 = 72
3x^2 = 72 + 3
3x^2 = 75
divide both sides by 3
x^2 = 25
x = 5
:
Check this
3(5^2-1) = 72