Malloy solved the equation −5x − 16 = 8; his work is shown below. Identify the error and where it was made. −5x − 16 = 8 Step 1: −5x − 16 + 16 = 8 + 16 Step 2: −5x = 24 Step 3: negative five times x over five = twenty-four over five Step 4: x = twenty-four over five
-5x - 16 = 8
-5x - 16 + 16 = 8 + 16 (step 1...correct)
-5x = 24 ( step 2...correct)
-5x/5 = 24/-5 (step 3...incorrect..he didn't divide both sides by -5)
x = -24/5
Answer:
Error in step 3
\(\frac{-24}{5}\)
Step-by-step explanation:
−5x − 16 = 8
Step 1: −5x − 16 + 16 = 8 + 16
Step 2: −5x = 24
Step 3: -5x/5 = -24/5
Step 4: x = 24/5
Step 1 and step 2 are correct
In step 3 we need to eliminate -5
so we divide both sides by -5
Malloy divided both sides by 5 instead of -5
so step 3 becomes
\(\frac{-5x}{5} =\frac{24}{-5}\)
step 4 : \(\frac{-24}{5}\)