SOLVE BY ELIMINATION. 3x+2y=3, 9x-8y=-2

Question

USE THE ELIMINATION METHOD TO SOLVE

Answer 1

Elimination method

Given equation 3x+2y = 3

Muliple to each side by negitive 3.

-9x-6y = -9----------> (1)

And 9x-8y = -2 ----------> (2)

To eliminate the x value add the equations (1) and (2).

-9x-6y = -9

9x-8y = -2

_________

-14y = -11

Divide to each side by negitive 14.

-14y/-14 = -11/-14

⇒ y = 11/14

Substitute the y value in (1).

-9x-6*11/14 = -9

-9x-66/14 = -9

Add 66/14 to each side.

-9x-66/14+66/14= -9+66/14

-9x = -9+33/7

-9x = (-63+33)/7

Divide to each side by negitive 9.

-9x/-9 = 30/7*-9

⇒ x = -10/21

Solution x = -10/21, y =11/14

Comments

Typo mistake in 22 ^nd  line of above solution.

-9x/-9 = -30/(7*-9)

⇒ x = 10/21

Solution x = 10/21, y =11/14.