s-t=3, s/3+t/2=6 solve equation by substitution method

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

s-t=3, s/3+t/2=6

Solution:

s-t=3, s/3+t/2=6

s-t=3-------(1)

s/3+t/2=6

make lcm for 3,2

(2s+3t)/6=6

2s+3t=36-----(2)

Let we take equation (1) and make s form

s-t=3

s=3+t-------(3)

substitute s value in equation (2)

2s+3t=36

2(3+t)+3t=36

6+2t+3t=36

6+5t=36

5t=36-6=30

t=30/5=6

t=6

substitute t value in equation (3)

s=3+t

s=3+6=9

s=9


Post details
CBSE Class 10 maths NCERT 10 Maths
Chapter : Pair of Linear Equations in Two Variables
Chapter 3
Exercise 3.2 (ii)

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