inequality -4(7x-3)<12
For this one, here's what to do: Add -4(7x - 3) to both sides. Then subtract 12 from both sides.
like this -4(7x - 3+ -4(7x - 3)<12+ -4(7x - 3)
Im so confused
Nope not like that
How will i do it?
If you add 4(7x - 3) to both sides, you get 0 < 12 + 4(7x - 3)
Now try subtracting 12 from both sides.
Not sure how to do that Like this maybe 0 < 12 + 4(7x - 3)-12?
Subtract 12 from BOTH SIDES. You only subtracted it from one side.
12-0<12+4(7x - 3)-12
Nope you added 12 to the other side rather than subtract it. You have MINUS 12 on one side and PLUS 12 on the other.
Tbh im confused
where do i subtract the 12
Here's what you should have if you subtracted 12 on both sides: 0 -12 < 12 - 12 + 4(7x - 3)
ok
what do i do now?
Simplify the expression. What is 0 - 12 and what is 12 - 12
0
Write the simplified expression after performing those operations.
0 -12 < 12 - 12 + 4(7x - 3) -12<0+4(7x-3)
which simplifies to -12 < 4(7x - 3)
Now, the next step is to apply the distributive property
ok -12 < 4(7x - 3) -12<4*28x-12 like this?
I think you meant to write -12 < 28x - 12
You already multiplied 4 times 7 to get 28 so there's no need to write 4 again.
yes
-12 < 28x - 12 do i solve 28x - 12 now?
You solve for x
The next step is to now add 12 to both sides.
ok -12+12 < 28x - 12+12 28x>0
28x<0*
I don't know what you did, but I did not mention anything about flipping signs
The inequality is like an arrow. You have to pay attention to where it is pointing.
28x>0 is correct. The other is not.
i didnt mean to flip the sign
Is there more to the problem?
The next step is to divide both sides by 28 to isolate x
ok
28x/28<0/28 x<0 this?
Why do you keep flipping signs?
I only tell you to perform a specific step
idk where the sign goes
I never said ever to flip a sign. That's what confuses students. So I was trying to show you how to do this without flipping the sign
oh
The answer is not x < 0
x<28?
Nope, not that either.
Go back to the last known correct step
oh flip the sign?
idk honestly
Flipping the sign is not a step in the solution I was showing you
You had it mostly right until the very end.
You got it wrong after I told you to divide both sides by 28
oh ok
28x/28<0/28 0<28 Like this idk
I didnt flip signs this time
The last known correct step was 28x > 0. Then if you divide both sides by 28 you get x > 0
Let me show you the full steps though.
Original Problem: -4(7x-3)<12 Add 4(7x - 3) to both sides to get: 0 < 12 + 4(7x - 3) Subtract 12 from both sides to get: -12 < 4(7x - 3) Apply the distributive property to get: -12 < 28x - 12 Add 12 to both sides to get 0 < 28x Divide both sides by 28 to get: 0 < x This next step is actually not flipping the sign. It is re-arranging the inequality so that x is on the LHS: x > 0 At no point did I flip a sign. Flipping the sign is an entirely different process.
Ok this is much clearer
In fact, you could leave it as 0 < x
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