How to solve equations with two unknowns

Trick Applicable For Calc Model : CASIO fx-991MS, CASIO fx-570MS, CASIO fx-100MS etc

Solving equations is frequently required in almost every mathematical problems.

As number of unknowns is equal to number of equations.

So at least two equations are required here.

Calculator takes the coefficients of x and y and returns the value of x and y.

Calculator can easily solve the following equations with coefficients known.

a₁x+b₁y=c₁
a₂x+b₂y=c₂

Example: Solve the following equations 3x-4y=7
-4x+8y+4=0 [Ans:(x,y)=(5,2)]

Solution:

Step-1:-(Mode initialization)
MODE >> MODE >> MODE >> 1(EQN) >> 2(Unknowns)

Step-2:-(Input coefficients)
3(a₁) >> = >> - >> 4(b₁,note b₁ is not 4,it's -4) >> = >> 7(c₁) >> = >> ->> 4(a₂) >> = >> 8(b₂) >> = >> - >> 4(c₂,note c₂ is -4 cause equation format that calculator follows is a₂x+b₂y=c₂) >> =(x=5) >> =(y=2)

Step-3:-(edit coefficient if necessary, suppose we have to put b₁=7,c₂=3)
(from last step) = >> = >> 7 >> = >> = >> = >> = >> 3 >> =(x=0.67) >>=(y=0.71)

(After solving equation return to COMP mode)
MODE >> 1