3
Review: points, lines, equation
Textbook: Part 1, lesson 3, pp. 8–9
GoalReview points, straight and curved lines; solving a simple equation.
New words
point · nuqtastraight line · to‘g‘ri chiziqcurved line · egri chiziqpoint of intersection · kesishish nuqtasi
Explanation
We mark a point with a capital letter: A, B. A straight line is drawn with a ruler, a curved line bends. When two straight lines cross, they have a common point. In an equation the unknown number is written as x.
Worked examples
Straight lines AC and BD cross at point O. O is their common point.
x − 15 = 54. Minuend = difference + subtrahend: x = 54 + 15 = 69.
Class activity
“Line hunters”: find objects with straight and curved lines in the classroom (door edge, wheel, clock). Children draw two columns in their notebooks and list what they find.
Practice
1
A basil plant is 37 cm tall. The mint is 5 cm shorter. How tall is the mint?
32
2
x − 15 = 54. x = ?
69
3
12 + 10 □ 18 + 0 (>, <, =)
>
4
Can two different straight lines have several common points?
No, at most one.