graph the linear system for 4x-y=5 4x+4y=-4

Question

please give me the anser

Answer 1

So you have two lines (linear equations).

Figure out the x and y intercepts of first line; plot points & draw line through them.

Repeat for second line.

Point of intersection is the solution of this problem.

This is a GENERAL METHOD. Memorize it.

 

One exception: if x and y intercepts of a line are both, as for example in y = 2x, then you will have to find some other point in addition to the Origin.

Answer 2

4x   - y  =  5

4x + 4y = -4

 

Subtracting the first equation from the second:

 

 4y - -y = -4 - 5

 

 4y + y = -4 + -5

 

 5y = -9

 

 y = -9/5

 

4x - (-9/5) = 5

 

4x + 9/5 = 5

 

20x + 9 = 25

 

20x = 16

 

x = 16/20 = 4/5

 

Plugging into the second equation:

 

4(4/5) + 4(-9/5) = 16/5 - 36/5 = -20/5 = -4

 

So the two lines meet at (4/5, -9/5) = (0.8, -1.8)

 

The first line is y = 4x-5

 

The second line is y = -1 -x = -x - 1

 

 

Plot these dots (0,-5) and (1.25,0); connect them

 

Plot these dots(0,-1) and ( -1,0) and (1,-2); connect them

 

Good luck