linear equation with two variables

the difference between two number is 40.

form a linear equation from above situation.

• x - y = 40

• x + y =40

• x = 40y

• y = 40x

 $x\ +4y=10$  
identify whether the above equation are linear equation with two variables

• yes 

• no

• not sure

 $x\ +4=10x$  
identify whether the above equation are linear equation with two variables

• yes 

• no

• not sure

 $x\ +4=10y^2$  
identify whether the above equation are linear equation with two variables

• yes 

• no

• not sure

 $a-7=10b$  
identify whether the above equation are linear equation with two variables

• yes 

• no

• not sure

 $2a=b$  
identify whether the above equation are linear equation with two variables

• yes 

• no

• not sure

In LA Hotel there are big room and small room. Each big room can stay by x people and each small room can stay by y people. In total, 3 small room and 2 big room and stay 17 people.

form a linear equation with two variables from above situation

• x - y = 17

• 3x + 2y = 17

• 3x - 2y = 17

• x + y =17

the total point score by Ali and Abu is 40 point.

form a linear equation with two variables from above situation

let y to be Ali's point
let x to be Abu's point

• x - y = 40

• x = 40

• x + y = 40

• x + 40=y

The total price of three apple and two orange is RM80

form a linear equation with two variables from above situation

let x to be price of apple
let y to be price of orange

• 2x - 3y = 80

• 2x + 3y = 80

• 3x + 2y = 80

• 3x - 2y = 80

the number of student in class 1A is twice the number of student in class 1S

form a linear equation with two variables from above situation

let x to be number of student in 1A
let y to be number of student in 1S

•  $\frac{x}{2}=y$  

• y - x =2

• y = 2x

• x = 2y