Question

Charlie solved an equation, as shown below:

Step 1: 5x = 30
Step 2: x = 30 – 5
Step 3: x = 25

Part A: Is Charlie's solution correct or incorrect? If the solution is incorrect, explain why it is incorrect and show the correct steps to solve the equation. (6 points)

Part B: How many solutions will this equation have?

Answer 1

Part A: Charlie's solution is incorrect. In step 2, Charlie subtracts 5 from 30, but that's not the correct operation to isolate x. Instead, he should divide both sides of the equation by 5. Here's the correct way to solve the equation:

Step 1: 5x = 30

Step 2: x = 30 / 5

Step 3: x = 6

So, the correct solution is x = 6.

Part B: This equation will have one solution. In general, a linear equation with one variable has exactly one solution.

Answer 2

The equation is 5x = 30

Part A

Charlies solution is incorrect

Step 2 is incorrect, 5 should not be subtracted

You should divide by 5 on both sides, leaving x on the left hand side and 30/5 on the right hand side

The correct steps are,

Step 1: 5x = 30

Step 2: x = 30/5

Step 3: x = 6

Part B

We see from part A, Step 3 (x=6) that the equation has 1 solution.

The equation will have 1 solution