1. 2x + y = 7 and 6x + 5y = 27*
Your answer

2x-5y=-1;6x-5y=27

Solution :

{x,y} = {7,3}

System of Linear Equations entered :

  [1]    2x - 5y = -1

  [2]    6x - 5y = 27

Graphic Representation of the Equations :

   -5y + 2x = -1        -5y + 6x = 27  

Solve by Substitution :

// Solve equation [2] for the variable  x

 [2]    6x = 5y + 27

 [2]    x = 5y/6 + 9/2

// Plug this in for variable  x  in equation [1]

  [1]    2•(5y/6+9/2) - 5y = -1

  [1]     - 10y/3 = -10

  [1]     - 10y = -30

// Solve equation [1] for the variable  y

  [1]    10y = 30

  [1]    y = 3

// By now we know this much :

   x = 5y/6+9/2

   y = 3

// Use the  y  value to solve for  x

   x = (5/6)(3)+9/2 = 7

Solution :

{x,y} = {7,3}

  Hope I helped! :)

true

explanation:

(0,-3) see attached graph

step-by-step explanation:

a. to solve the system, graph the two equations.

x = y+3 becomes y=x-3 has m=1/1 and b=-3. start at (0,-3) on the y-axis and plot a point. then move up 1 unit and 1 unit to the right. plot a point and connect.

y=-4x+3 has m =-4/1 and b=-3. start at (0,-3) on the y-axis and plot a point. then move down four units and to the right 1 unit. plot a point and connect.

the solution is the point (x,y) where the two lines intersect. by the graph below it is (0,-3).

b. to solve by substitution, substitute y = -4x-3 into x= y+3

x= (-4x-3) +3

x=-4x

5x=0

x=0

now substitute x = 0 back in to find y.

y= -4(0)-3

y=0-3

y=-3

solution is (0,-3)

c. use elimination by adding the equations together.

x-y=3

4x+y=-3

5x=0

x=0

then substitute into one equation to find y.

y=-4(0)-3

y=-3