# Linear Equations – Written as Matrix

System of Linear Equations

A supermarket is selling three different fruits, i.e. apple, orange and pear.

The price of an apple is RM x, the price of an orange is twice of an apple, and the price of a pear is RM y.

Two different stalls, stall A and stall B get their supplies from this supermarket.

Stall A bought 350 apples, 200 oranges and 300 pears and pays RM 680. Stall B bought 400 apples, 150 oranges and 250 pears and pays RM 530.

i) Based on the above information, form a system of linear equations.

ii) Write the above linear equations in the form of a matrix equation

### Comments for Linear Equations – Written as Matrix

 Sep 01, 2012 Linear Equations by: Staff Answer:i) Based on the above information, form a system of linear equations. The price of an apple is RM x   x = price of an applethe price of an orange is twice of an apple   2x = price of an orangeprice of a pear is RM y   y = price of a pearSummary of prices   x = price of an apple   2x = price of an orange   y = price of pearStall A bought 350 apples, 200 oranges and 300 pears and pays RM 680.     (350 apples)*x + (200 oranges)*2x + (300 pears)*y = 680   750x + 300y = 680Stall B bought 400 apples, 150 oranges and 250 pears and pays RM 530.     (400 apples)*x + (150 oranges)*2x + (250 pears)*y = 530   400x + 300x + 250y = 530   700x + 250y = 530system of linear equations   750x + 300y = 680    700x + 250y = 530 ii) Write the above linear equations in the form of a matrix equation   750x + 300y = 680   700x + 250y = 530   │ 750x + 300y │    │ 680 │   │                    │ = │        │   │ 700x + 250y │    │ 530 │   │ 750 + 300 ││ x │    │ 680 │   │                    ││    │ = │        │   │ 700 + 250 ││ y │    │ 530 │Coefficient matrix   │ 750 + 300 │   │                  │   │ 700 + 250 │Variable matrix   │ x │   │    │   │ y │Constant matrix   │680│   │     │   │530│Thanks for writing. Staff www.solving-math-problems.com