<span>let y = sec^2 ( pi x )
y' = 2 sec ( pi x ) sec( pi x ) tan ( pi x ) pi
y' = 2pi sec^2 ( pi x ) tan ( pi x )
y''= 2pi sec^2 ( pi x ) * sec^2 ( pi x ) * pi + 2pi tan ( pi x ) * 2pi sec^2 ( pi x ) tan ( pi x )
y'' = 2 pi^2 sec^4 ( pi x ) + 4 pi^2 sec^2 ( pi x ) tan^2 ( pi x )</span>
You draw a straight line and then put your number on the line. If you have to find a negative number, you can just go below zero. Positive numbers on a number line are always above zero. Hope this helps!
9 = 2(6) - b
9 = 12 - b
-3 = b
300 messages would have to be sent or received in order for the plan to cost same each month.
Step-by-step explanation:
Given,
Cost per month = $30
Per text sent or received charges = $0.10
Let,
x be the number of texts sent or received.
A(x) = 0.10x+30
A comparable plan costs = $60 per month
Text messages are unlimited.
B(x) = 60
For the two plans to cost equal;
A(x) = B(x)

Dividing both sides by 0.10

300 messages would have to be sent or received in order for the plan to cost same each month.
Keywords: function, addition
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