What is Algebraic Replacement?
Algebraic replacement means replacing characters (or variables) with numbers. Algebra uses characters such as X, Y, A to present unknown numbers.
When you exchange it, you will set a number instead of this letter. We call it a “variable” because it can change Expression.
Alternatives help us:
1. Find the value of the expression.
2. Check if the equation is true or wrong.
3. Solve real mathematics problems. Look at the expression.
2. You can see which numbers to get for the variable.
3. Replace the variable with a number.
4. Do math! Answer: 15
Top 2: Variable
Replace with expressions
Sometimes expressions have multiple variables, like x and y.
Example:
Formula: x + y
Character=2 and y = 3
Alternative:
x + y = 2 + 3 = 5
Formula: 2x + 3y
be x = 1 and y = 4
Replacement:
2x + 3y = 2 1 + 3= 2 + 12 = 14
Correct order (Bodmas or Pemas). 16
Another example:
Formula: (x + 2)(y1)
Let x = 4, y = 3
Alternative:
(4 + 2)(31)= 62 = 12
12
The cost of each pen is p-rupies. How much do you pay if you buy a 3 pen?
Don’t forget to multiply:
oExpression: 3x, x = 4
If it’s wrong: 3x = 34
Right: 34 = 12br>2.
False operation order:
Expression: 2(x+3)
x=5
Incorrect: 2x+3 = 2 raw 5+3
Right: 2(5+3) = 2(5+3)
Expression: x+y
x=2,y=3
Don’t forget to replace both characters!
You can use the alternative to see if the number is the solution.
Example:
A car travels d = 60 km. It’s a few hours.
How far will the car go if it drives for 3 hours?
