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

Error in step 3

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

step 4 :  

b.) 160 miles on a 5 gallons car

step-by-step explanation:

240/10=24 miles/gallon

160/5=32 miles/gallon

30/1=30 miles/gallon

168/6= 28 miles/gallon

32 miles/gallon is the most amount, so this is the best.

mr. flanders’ class sold 47 doughnuts and   mr. rodriquez’s class sold 38 cartons of milk

step-by-step explanation:

let x be the number of doughnuts sold by mr. flanders’ class and y be the number of cartons sold by mr. rodriquez’s class.

1. together, the classes sold 85 items, then

x+y=85.

2. both classes earn earned $104.49 for their school. if doughnuts were sold for $1.35 each, then x doughnuts costed $1.35x. if cartons of milk were sold for $1.08 each, then y cartons costed $1.08y. hence,

1.35x+1.08y=104.49.

3. solve the system of two equations: