Constructing_and_Solving_Equations_Grade7_8.pptx

Constructing_and_Solving_Equations_Grade7_8.pptxConstructing_and_Solving_Equations_Grade7_8.pptx

1. Mrs. Areej Ahmed Constructing and Solving Equations Grade 7 & 8 Math Lesson L 2.5

2. Warm Up 2

3. Lesson Objectives I will understand how to write and solve equations

4. Introduction • Equations are mathematical statements that show two expressions are equal. • Constructing equations helps us model real-world problems. • Solving equations means finding the unknown value that makes the equation true.

5. Steps for Solving Equations 1. Write down the equation. 2. Simplify both sides if necessary. 3. Use inverse operations to isolate the variable. 4. Check your solution by substituting it back into the original equation.

6. Example Problem 1 Rectangle with sides: 2(y + 3) and 5x – 3 Equation: 2(y + 3) + 5x – 3 = 37 Solve for x and y. Strategy: Set equal lengths equal to each other.

7. Example Problem 2 Emily thinks of a number. She multiplies it by 3, then adds 8. The answer is 23. Equation: 3x + 8 = 23 Solve: x = 5.

8. Triangle Angle Problem Angles of a triangle add up to 180°. Example: (2n + 5) + (n – 5) + 60 = 180 Simplify: 3n + 60 = 180 Solve: n = 40. Angles: 85°, 35°, 60°.

9. Practice Questions 1. Solve: 4x – 7 = 13 2. Solve: 2(y + 4) = 20 3. The sum of two consecutive numbers is 37. Find the numbers. 4. A rectangle has length (3x + 2) and width (x + 5). If the perimeter is 40, find x.