Question

solve the pair of linear equations 2x+3y=9, 3x+4y=5​

Answer 1

Step-by-step explanation:

Multiply, eq-1 by 3

3*(2x+3y) = 27

6x+9y = 27

Multiply, eq-2 by 2

2*(3x+4y) = 10

6x+8y = 10

Subtracting both results,

(6x+9y) - (6x+8y) = 27 - 10

6x-6x + 9y-8y = 17

y = 17

Put in eq-1,

2x + 3*17 = 9

2x = 9 - 51

x = -21

Answer 2

Answer:

y= 17, x= -21.

Step-by-step explanation:

The 1st equation is 2x + 3y = 9

Now we will multiply the equation by 3, so:

(2x + 3y)3 = 9*3

6x + 9y = 27.

The 2nd equation is 3x + 4y = 5

Now we will multiply the equation by 2, so:

(3x + 4y)2 = 5*2

6x + 8y = 10.

6x in both equation is common, so we will subtract 6x and will get y's value.

6x + 8y - (6x + 9y) = 10 - 27

-y = -17, y=17.

So, if y =17, then x=?

2x + 3y = 9.

2x + 3*17 = 9

2x = -42

x= -21.