Basic Science & technology for Junior secondary student’s - Lagos

I give classes online.
Mathematics: Algebraic Simplification:it involves combining like terms to make an expression simpler.
Like terms
Like terms are terms that have the same variable(s) with the same exponents.
Rules for simplifying Algebraic Expressions.
1. Combine like terms
2. Remove parentheses
3. Simplify numerical coefficients
Examples:
Simplify:
a. 2x + 3x
b. 2(x+3)
c. X2 + 2x2
Solutions
a. 2x +3x = 5x
b. 2(x+3) = 2x +6
c. X2 + 2x2 = 3x2.

Try these:
1. 3x + 2x - 4x
2. 2y2 + 5y2 - y2
3. X2 + 3x2 - 2x
4. 4z - 2z + z

SCIENCE
TOPIC: POLLUTION
Pollution is the introduction of harmful substances or contaminants into the environment, causing negative effects on the natural world, human health, and the economy.
TYPES OF POLLUTION
1. Air Pollution: The release of harmful substances into the atmosphere.
2. Water Pollution: The contamination of water bodies by rivers, lakes, and oceans.
3. Soil Pollution: The contamination of soil with harmful substances.
4. Noise Pollution: Excessive noise that can harm human.
5. Light Pollution: Excessive light that harm health.
CAUSES OF POLLUTION
1. Industrial activities
2. Vehicle emission
3. Agricultural activities
4. Waste management
5. Climate waste
EFFECTS OF POLLUTION
1.Environmental damages
2. Human health
3. Economic impact
4. Social impact
Try this:
1. Define pollution based on the given notes.
2. Highlight 4 types of pollution and explain one
TAKE HOME
1. Enumerate 3 causes of pollution

SUBJECT 3:
TOPIC: WAVE MOTION
Introduction
Wave motion is a means of transferring energy. In such a motion in a material medium, particles of the medium vibrate about their positions of equilibrium. The wave energy energy is carried forward but not the medium.
When we throw a stone into a pool of water, circular waves form and move outward. Waves will also travel along a cord or rope that is stretched out straight on a table if we vibrate one end back and forth. Water waves and waves on a cord, are two common examples of wave motion. In this notes we will concentrate on Mechanical waves-- waves that travel in a material medium.
All types of waves have as their source a vibration. Water waves for example move with a recognisable velocity, but each particle of the water itself merely oscillates about an equilibrium position. This is easily seen when we observe leaves on pond as waves pass by. The leaves are not carried forward by the waves, but simply move up and down about an equilibrium point because this is the motion of the water itself. This is a general feature of waves: waves can move over large distances but the medium (e.g. the water or the cord) itself has only a limited movement. A wave consists of oscillations that move without carrying matter with them. Such up-and-down movement or vibration or oscillation of the medium (e.g. water) which causes waves is an example of wave motion.
A wave motion is a process of transferring a disturbance (in form of kinetic energy) from one point to another in a medium without any transfer of particles of the medium.
A wave is a disturbance which travels through a medium transferring energy from one point to another without causing any permanent displacement of the medium.
TAKE HOME
Briefly explain the term waves with examples.