Identify the line that contains the error in this solution and correct the work for that line.
Line 1: -2(x + 1) - 3 ≥ 11 Line 2: -2x + -2 - 3 ≥ 11 Line 3: -2x + -5 ≥ 11 Line 4: -2x ≤ 16 Line 5: x ≤ -8
Do you know the first step?
Simplify like terms?
Well lets start with line one, You want to solve it just like an equation. Step 1 would be to distribute.
-2(x + 1) - 3 ≥ 11 -2x - 1 - 3 ≥ 11
okay. -2x - 1 - 3 1 - 3 = - -1
If the answer is -1, then we went wrong on line two.
-2(x + 1) - 3 ≥ 11 -2x - 1 - 3 ≥ 11 -2x - 4 ≥ 11 -2x ≥ 11 + 4 -2x ≥ 15 -2x 15 --- ≥ ---- -2 -2
Line 4: -2x ≤ 16 Line 5: x ≤ -8 We see here that -2 is on the left, upon dividing by a negative the signs switch, also. We went wrong on line 5.
so we should add three to both sides at line 2?
Line 1: -2(x + 1) - 3 ≥ 11 (Original equation.) Line 2: -2x + -2 - 3 ≥ 11 (Distributed) Line 3: -2x + -5 ≥ 11 (Added like terms.) Line 4: -2x ≤ 16 (Added +5 to 11.) Line 5: x ≤ -8 (Divided by -2, but the signs didn't switch. Line: 5 is wrong.) The equation should say: \[x \ge -8\]
Remember, that upon dividing by a negative number the sign switches.
okay, I understand now. Thank you so much. :)
I always return the favor of a medal.
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