Answer :

thisisbenmanley
To do substitutions, you take a phrase equal to one letter and you put that phrase in the other equation.  The equations we're working with are

y = 6x - 11
-2x - 3y = -7

So it's already set up for us:  it gives us what y equals; 6x - 11.  So, just plug 6x - 11 into the y of the other equation

-2x - 3(6x - 11) = -7           Then you distribute the -3 on the outside of the                                                    parentheses to the 6x and the -11 on the inside.
-2x - 18x + 33 = -7            Move a few numbers around and add like terms.
-20x = -40                        Then, just solve for x by dividing by -20.
x = 2

So, now you have the x: 2.  Use that to find the y in y = 6x-11 by plugging in the 2 for the x.

y = 6(2) - 11
y = 12 - 11
y = 1

So, the answer is x = 2 and y = 1, or the ordered pair (2, 1)
logo88
y=6x-11 (label equation 1)
-2x-3y=-7 (label equation 2)

sub 1 into 2
-2x-3(6x-11)=-7
-2x-18x+33=-7 (i expanded the brackets)
-20x+33=-7 (i simplified by adding like terms)
-20x=-40 (i subtracted 33 to both sides)
x=2 (i divided by -20 to both sides)
sub x=2 into 1
y=6(2)-11
y=12-11
y=1
therefore x=2 and y=1

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