Question

Solve: 2x + 7y=39 and 3x + 5y-31 =0.Hence find m, if m=2x+3y. ​

Answer 1

Answer:

m = 19

Explanation:

Given equations,

→ 2x + 7y = 39. . . . . (i)

→ 3x + 5y - 31 = 0 or, 3x + 5y = 31 . . . . (ii)

Multiplication,

• eq.(i) by 3
• eq.(ii) by 2

New equations,

→ 6x + 21y = 127

→ 6x + 10y = 62

By elimination method,

6x + 21y = 127

6x + 10y = 62

→ 11y = 55

→ y = 55/11

→ y = 5

Substituting ‘y’ in eq.(i) :-

→ 2x + 7y = 39

→ 2x + 7(5) = 39

→ 2x + 35 = 39

→ 2x = 39 - 35

→ 2x = 4

→ x = 4/2

→ x = 2

Hence the value of :-

• x = 2
• y = 5

Finding ‘m’ :-

→ m = 2x + 3y

→ m = 2(2) + 3(5)

→ m = 4 + 15

→ m = 19

∴ The value of ‘m’ is 19.