how do i solve an equation that is 1x+4y=6 when y=-x+3

Question

none 

Answer 1

You are given 2 equations. 

 

1x + 4y = 6             eq1      

y = -x + 3               eq2

 

 

In one of the equations, the coefficient of x is 1, so we can rewrite that equation as

 

x + 4y = 6             eq1

 

 

The value of y is defined as -x + 3 in the other equation.  We can substitute this equation into eq1.

 

x + 4(-x + 3) = 6

 

 

Now we have an equation that only consists of one variable.  This makes it easier to solve.  We can solve for x from this equation.

 

x - 4x + 12 = 6

-3x + 12 = 6

-3x = -6

   x = 2

 

Substitute this value of x into eq2.  This will allow us to solve for the other variable y.

 

y = -2 + 3

y = 1

 

 

Your solutions are

 

x = 2

y = 1

Answer 2

1x+4y=6 when y=-x+3

replace y by -x+3

x+4(-x+3)=6

x-4x+12=6

-3x+12=6

-3x=6-12

-3x=-6

x=-6/-3

x=2