Question

9x-4y=20 7x-3y=20 by substitution method​

Answer 1

Question

9x-4y=20

7x-3y=20

Solve by substitution method.

Answer

9x-4y=20 ------(I)

7x-3y=20-------(ii)

Multiplying equation (I) by 3 and equation (ii) by 4 we get,

3(9x)-3(4y)=3(20)

=>27x-12y=60

4(7x)-4(3y)=4(20)

=>28x-12y=80

Now,

27x-12y=60

28x-12y=80

=> x = 20

Substituting the value of x in equation (I)

9x-4y=20

=>9×20-4y = 20

=>180-40y = 20

=> -40y = -160

=> -y = = -120

=> y = 120

Let's verified!!

Taking the equation (I) , we get

9x-4y=20

=>9×20-4×120=20

=>180-160 = 20

=> 20 = 20

Hence,LHS = RHS

Answer 2

Answer:

20 answer you have to practice