0.2x+0.3y=1.3, 0.4x+0.5y=2.3

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 1. Solve the following pair of linear equations by the substitution method.

(iv) 0.2x+0.3y=1.3, 0.4x+0.5y=2.3

Solution:

0.2x+0.3y=1.3

Multiply both sides with 10

10(0.2x+0.3y)=10x1.3

2x+3y=13----------(1)

0.4x+0.5y=2.3

Multiply both sides with 10

10(0.4x+0.5y)=10x2.3

4x+5y=23----------(2)

Let we take equation (1) and make x form

2x+3y=13

2x=13-3y

X=(13-3y)/2--------(3)

Substitute x value in equation (2)

4x+5y=23

4(13-3y)/2=5y=23

(52-2y)2+5y/1=23

(52-12y+10y)/2=23

(52-2y)/2=23

52-2y=46

2y=52-46

2y=6

Y=3

Substitute y value in equation (3)

x=(13-3y)/2

x=(13-3x3)/2=(13-9)/2=4/2=2

x=2


Post details

Chapter: Pair of Linear Equations in Two Variables

Chapter 3

Exercise 3.2

Question 1.(iv)

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