Create algebraic expressions and evaluate them by substituting a given value for each variable(ACMNA176)
LO:To evaluate algebraic expressions
- What an expression is
- The four basic operations of numeracy
- That expressions can be created and solved using substituting methods.
- I can evaluate algebraic expressions
- What is an expression?
- How can algebraic expressions be evaluated?
Expressions and Equations
An expression is one-half of a equation.
x – 6 is an expression.
x – 6 = 10 is an equation.
Evaluating an Expression
To evaluate an expression, means to solve for the “missing piece”.
To evaluate an expression, we substitute (or replace) each pronumeral with a number and then work out the value.
Make sure you follow the correct order of operations when evaluating an expression (BODMAS)
X + 6, evaluate the value of the expression when we substitute (replace) x for 10.
10 + 6 = 16.
3k + 5, evaluate the value of the expression when we substitute k for 5.
3 x 5 + 5 = 20. (remember multiply before add)
Real-life Example of Algebra
Evaluating Expressions Videos
My Maths 7
Ex 5D pg. 253 Q. 1-5
My Maths 8
Ex 4B pg. 185 Q. 1-8