Question

system of linear equation | Slope(m) | Y-intercept | Graph
×-y=4
x+4y=5

x-2y=4
x-2y=4

5x-y=5
5x+y=20​

Answer 1

Elimination Method:

- 2X + y = 4

3X + y =4

3X + 4Y = 5

-4(-2X- 4Y = 4 )

11 X = 5 -16 = -11

X = -11/ 11 = -1

Substitute X = -1 into 2nd equation

- 2( -1) + Y = 4

Y = 4 -2 =2

Substitution method

3X + 4Y = 5

-2X + Y = 4

Y = 2X +4 from 2nd equation:

3X + 4( 2X + 4) = 5

11X + 16 = 5

11X = -11 X = -1

Substitute in 2nd equation:

-2( -1) + Y = 4

Y = 2

To graph :

3X + 4Y = 5 3( 0) + 4Y = 5 Y intercept = 5/4 ( 0 , 5/4)

3 X + 4 (0 ) = 5 X intercept = 3/5 ( 3/5, 0)

Connect the 2 points together, and have the graph

- 2X + Y = 4 -2( 0) + Y = 4 ( 0 , 4 ) is Y intercept.

-2X + 0 = 4 (-2, 0 ) is X intercept

Connect 2 points and get the graph of the line

Observe that intersect point is :

( -1 ,2 )