Question

Solve fe following equations by Cramer's rule. ix-4y =9, 3x +2y = -11​

Answer 1

Answer

x=−1,y=−4

Explanation

Given equations are 3x+2y+11=0 and 7x−4y=9

⟹3x+2y=−11 and 7x−4y=9

By Cramer's rule,

D=

∣

∣

∣

∣

∣

∣

3

7

2

−4

∣

∣

∣

∣

∣

∣

=−12−14=−26

D

x

=

∣

∣

∣

∣

∣

∣

−11

9

2

−4

∣

∣

∣

∣

∣

∣

=44−18=26

D

y

=

∣

∣

∣

∣

∣

∣

3

7

−11

9

∣

∣

∣

∣

∣

∣

=27+77=104

Now, x=

D

D

x

=

−26

26

=−1

y=

D

D

y

=

−26

104

=−4

Hence, x=−1,y=−4.