inequalities (1 Viewer)

[jannny]

I dunno I dno how u get the answer.

m^2 - 144 > 0

isnt it supposed to be

m^2 > 144

then

m > 12 or m >-12 ?

but the answer states taht

m < -12 and m < 12

 

[watatank]

I dunno I dno how u get the answer.

m^2 - 144 > 0

isnt it supposed to be

m^2 > 144

then

m > 12 or m >-12 ?

but the answer states taht

m < -12 and m < 12

graph it on a cartesian plane (instead of thinking of it like x,y in your case maybe m, n?). wherever the resultant curve is above the axis, thats your answer. i think it would probably be m > 12, m < -12.

 

[darkliight]

m^2 - 144 > 0 implies (m-12)(m+12) > 0.

Now, we have two numbers that must multiply to give a positive number, ie, both numbers must be positive or both numbers must be negative.

Both numbers are positive when m > 12. Similarly, both numbers are negative when m < -12.

Another way to do it would be to just solve m^2 - 144 = 0. The two solutions will divide your number line into three segments. Test a number in each segment and see what you get. This is essentially the same as graphing the curve, just without the annoyance of having to graph something.

 

[beentherdunthat]

ALWAYS draw the graph for inequalities. ALWAYS.