KOLEKSI SIRI PERTAMA QUANTUM COOL-ACTIVE: MATHEMATICS SIMPLIFIED : FROM BASICS TO BRILLIANCE

KeypointsKeypoints NotesNotes

SummarySummary

LINEAR EQUATIONSLINEAR EQUATIONS

LINEAR EQUATION IN THREE VARIABLE

To solve this, can use both elimination

method and substitution method :

x + 2y + 3z = 2 ....(1)

x + 3y + 6z = 4 ....(2)

2x + 6y + 11z = 6 ....(3)

(1) x 2 : 2x + 4y + 6z = 4 ....(4)

(2) x 2 : 2x + 6y + 12z = 8 ....(5)

(4) - (3) : - 2y - 5z = -2 ....(6)

(5) - (3) : z = 2

Substitute z = 2 into (6)

• 2y - 5(2) = -


• 2y = 8
  y = - 4

Substitute y and z into (1)

x + 2(-4) + 3(2) = 2

x - 2 = 2

x = 4

x = 4, y = - 4 and z = 2

STEP BY STEP

1 .To start with,

elimination method

can be used to

eliminate one of the

variables.

2 .Now, only two

variables left. Solve

the simultaneous

equation using one

of the methods.

3 .Substitute the

value from the first

solution and solve it

to get other two

value of variables.

Linear equation is about :

straight line when its graphed

each term has an exponent of 1

the equation has an equality symbol