Solve for 2 unknowns : 2a+b=5; 3a+2b=9

Let us take the first equation first

2a + b = 5

Then

b = 5 - 2a

Now we have to put the value of b from the first equation in the second equation. Let us take the second equation now.

3a + 2b = 9

3a + 2 (5 - 2a) = 9

3a + 10 - 4a = 9

- a = 9 - 10

- a = - 1

a = 1

Now let us put the value of a in the first equation.

2a + b = 5

2 (1) + b = 5

2 + b = 5

b = 5 - 2

= 3

So the value of the unknown variable a is 1 and the value of the unknown variable b is 3.

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