Solve the Decimal Equation: Finding the Number in x - 0.8 = 0.1

Video Solution

Solution Steps

00:00 Identify which of the following answers is correct

00:03 Insert each of the potential answers into the expression in order to verify which of them is correct

00:11 Use vertical addition to calculate the problem

00:18 Insert one of the answers into the expression and proceed to calculate

00:32 We can see that the first option doesn't fit, let's move on to the second one:

00:40 Let’s apply the same method as before and proceed to check

00:44 Insert one of the answers into the expression and calculate

00:54 We can see that the second option fits, let's move on to the third one

01:01 Once again apply the same method as before and proceed to check

01:06 Insert one of the remaining answers into the expression and calculate

01:19 We can see that the third option doesn't fit, let's move on to the fourth one

01:26 Apply the same method as before and proceed to check

01:31 Insert the remaining answer into the expression and proceed to calculate

01:56 We can see that the fourth option doesn't fit

02:02 This is the solution

Step-by-Step Solution

Let's solve the equation $? - 0.8 = 0.1$ by isolating the unknown variable:

Step 1: Write the equation:

$? - 0.8 = 0.1$

Step 2: To find the value of '?', add $0.8$ to both sides of the equation as follows:

$? - 0.8 + 0.8 = 0.1 + 0.8$

Step 3: Simplify both sides:

The left side simplifies to $?$ because $-0.8 + 0.8 = 0$ .

The right side becomes $0.1 + 0.8 = 0.9$ .

So, $? = 0.9$ .

Therefore, the missing value is $0.9$ .