Which graph shows the solution for the inequality -7x-11

Question

Which graph shows the solution for the inequality -7x-11<-109

saifoo.khan · Answer

Did you tried solving?

anonymous · Answer

here are the graphs

anonymous · Answer

yeah but it doesnt seem right

saifoo.khan · Answer

What did you got?

anonymous · Answer

-7

saifoo.khan · Answer

$$-7x-11<-109$$
$$-7x < -109 + 11$$
$$-7x < -98$$

anonymous · Answer

umm....i dont get it and did u look at the attachments??????????????

anonymous · Answer

Akeller, first solve the equation for x just as you would if the < sign was an = sign. Algebraic manipulation still works with inequalities.

saifoo.khan · Answer

Moving along:
$$0 < -9x + 7x$$Flip action:
$$7x - 98> 0$$$$7x > 98$$$$x > 14$$

anonymous · Answer

do wat @Traxter

saifoo.khan · Answer

And @Traxter is correct.

saifoo.khan · Answer

You have to calm down, solve the given inequality first, rather than rushing towards the attachments.

anonymous · Answer

Rearrange the equation and simplify with x on one side. A lot of students think that algebra with inequalities is different than usual algebra but it's exactly the same. The only thing you have to watch out for is that you change the inequality (> to < or vice versa) if you multiply or divide by a negative number.

anonymous · Answer

okay so wat do i do first

anonymous · Answer

So in the same way that if you were solving -7x-11=-109, you would start off by moving the constants to one side and dividing to get x on its own.

anonymous · Answer

so you would add 11 to both sides

anonymous · Answer

Yes that would be the first step. What's next?

anonymous · Answer

then you would divide -7 to the answer of -109+11 which is -98

anonymous · Answer

which is a +14

anonymous · Answer

Excellent :) now this is the only thing different with the algebra you're used to. When you divide (or multiply) by a negative number you have to flip the inequality. What do you end up with?

anonymous · Answer

x>14

anonymous · Answer

Well done :)

anonymous · Answer

so what graph would it be

anonymous · Answer

Do you know what sort of circle you use to represent a strict inequality on a number line (i.e. >, where you don't include the value at the circle)?

anonymous · Answer

yeah for <> open circle
and the other ones closed circle i think it is the first graph

anonymous · Answer

You're right, and it is indeed the first graph.

anonymous · Answer

thanks

anonymous · Answer

No problem, well done for doing most of the work yourself :)