Question

3x - y = 15 , 4x + 4y =17 , 6x +2y =1​

Answer 1

Step-by-step explanation:

Disclaimer: There is error in the Q. In (II) there should have been 2x - 3y = 12

5x + 3y = 9 -----(I)

2x - 3y = 12 ----- (II)

Add (I) and (II)

7x = 21

x = 3

Putting the value of x = 3 in (I) we get

5(3)+3y=9⇒15+3y=9⇒3y=9-15=-6⇒y=-2

Thus, (x, y) = (3, -6).

Answer 2

Answer:

1

Step-by-step explanation:

i) x + y =5 and 2x –3y = 4

By elimination method

x + y =5 ... (i)

2x –3y = 4 ... (ii)

Multiplying equation (i) by (ii), we get

2x + 2y = 10 ... (iii)

2x –3y = 4 ... (ii)

Subtracting equation (ii) from equation (iii), we get

5y = 6

y = 6/5

Putting the value in equation (i), we get

x = 5 - (6/5) = 19/5

Hence, x = 19/5 and y = 6/5

By substitution methodx + y = 5 ... (i)

Subtracting y both side, we get

x = 5 - y ... (iv)

Putting the value of x in equation (ii) we get

2(5 – y) – 3y = 4

-5y = - 6

y = -6/-5 = 6/5

Putting the value of y in equation (iv) we get

x = 5 – 6/5

x = 19/5

Hence, x = 19/5 and y = 6/5 again