Solving Algebraic Equations
Primary 7 Mathematics Introduction to Algebra Northern Ireland Curriculum
What is Algebra?
Algebra uses letters to represent unknown numbers We call these letters 'variables' (like x, y, z) It helps us solve real-world problems Think of it as mathematical detective work!
Can you solve this puzzle?
If I have some sweets and I eat 3 of them, I have 7 left. How many sweets did I start with? Let's call the unknown number 'x' So: x - 3 = 7
What is an Equation?
An equation shows that two things are equal It has an equals sign (=) in the middle Both sides must have the same value Like a balanced scale - both sides weigh the same
Solving Different Types
{"left":"Addition Equations: x + 5 = 12 (switch sides, switch signs. Plus will turn to minus)\nSubtraction Equations: x - 3 = 9 ( Minus will turn to plus here)\n\nMultiplying Equations: 3x = 24 (multiply will turn to divide)\n\nx = 24 divided by 3. x = 8","right":"Always switch negative/positive numbers when moving to the other side of the equation!\n\n\n\n"}
Your Notes
More Complex Equations - 4x - 8 = 40 4x = 40 + 8 4x = 48 x = 48 divided by 4 x = 12
Let's Practice Together!
Solve: x + 8 = 15 What operation do we use? Show your working on mini whiteboards Remember to check your answer!
Key Points to Remember
Equations are like balanced scales When we swich numbers from one side to another, we switch their signs e.g. +5 will turn to -5 Show your working out clearly