Question

2x-3y=5,3x-y=2. Solve by elimination​

Answer 1

Answer:

2x + 3y = 5

So 6x + 9y = 15 (equation 1)

3x + y = 4

6x + 2y = 8 (equation 2)

(6x + 9y) - (6x + 2y) = 15 - 8

7y = 7

y = 1 (equation 3)

Substitute y = 1 into equation 2,

3x + (1) = 4

x = 1

(x, y) = (1, 1)

Substitution

2x + 3y = 5 (equation 1)

3x + y = 4, so y = 4 - 3x (equation 2)

Substitute equation 2 into equation 1,

2x + 3(4 - 3x) = 5

2x + 12 - 9x = 5

12 - 7x = 5

12 - 5 = 7x

7x = 7

x = 1 (Equation 3)

Substitute equation 3 into equation 2,

y = 4 - 3(1) = 1

(x, y) = (1, 1)

Graphical method

Find the x and y intercept of each line, draw the lines on the same set of cartesian coordinates, and look at where the lines cross.

(x, y) = (1, 1)