Question

if (3a+2b)=12 and (2a+4b)=10 then find th value of a and b

Answer 1

Answer:

a = 7/2

and b = 3/4

Step-by-step explanation:

we have,

3a+2b = 12 ..... (1)

and 2a+4b = 10 ..... (2)

multiply eq. (1) by 2 and we get....

6a+4b = 24

2a+4b = 10

- - -

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4a = 14

a = 7/2

so by putting it in eq. (1)

3(7/2)+2b = 12

2b = 12-21/2

2b = (24-21)/2

b = 3/4

for verifying we take eq. (1)

3(7/2)+2(3/4)

= (42+6)/4

= 48/4

= 12

hence, a = 7/2

and b = 3/4 .....ans.

Answer 2

Given system of Equations,

3a + 2b = 12..........[1]

and,2a + 4b = 10...........[2]

•Multiplying equation [1] by 2 and equation [2] by 3,we get:

6a + 4b = 24..........[3]

and,6a + 12b = 30.......[4]

•Subtracting equations [3] and [4],we get:

(6a + 12b) - (6a + 4b) = 30 - 24

→8b = 6

→b = 6/8

→b = 3/4

•Putting b = 3/4 in [1],we get:

3a + 2(3/4) = 12

→3a + 3/2 = 12

→3a = 12 - 3/2

→3a = 21/2

→a = 21/6

→a = 7/2

Thus,a and b are 7/2 and 3/4 respectively