Question

3a+4b=43, - 2a+3b=11

Answer 1

Hi ,

3a + 4b = 43 -----( 1 )

-2a + 3b = 11 ----( 2 )

Multiply equation ( 1 ) with 2 and

equation ( 2 ) with 3 , we get

6a + 8b = 86 ---( 3 )

-6a + 9b = 33 ---( 4 )

Add equations ( 3 ) and ( 4 ) we get,

17b = 119

b = 119/17

b = 7

Put b = 7 in equation ( 1 ) , we get

3a + 28 = 43

3a = 43 - 28

3a = 15

a = 15/3

a = 5

Therefore ,

a = 5 , b = 7

I hope this helps you.

: )

Answer 2

3a +4b = 43 ----1equation
-2a +3b = 11 ----2equation
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[ 3a +4b =43] × 2
[-2a +3b = 11] × 3

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6a + 8b = 86
-6a + 9b = 33
___________
0 + 17b = 119
___________

b = 119/17

b = 7

Now, putting the value of 'b' in 1equation.

3a +4(7) = 43

3a + 28 = 43

3a = 43-28

3a = 15

a = 15/3

a = 5
____________________

b = 7
a = 5

_____________________

I hope this will help you

-by ABHAY