88.0k views
1 vote
7x - y = 7
x + 2y = 6

1 Answer

2 votes
Answer is ( 1 1/3, 2 1/3 )

Graph attached

You can also solve by substitution methods

Substitution:

Change the 2nd equation so x is on one side by subtracting 2y from both sides

Now we have

7x -y = 7
x = -2y + 6

Substitute the value of x in the 2nd equation for x in the first equation

7 (-2y + 6) - y = 7
Multiply

-14y + 42 -y = 7
Simplify

-15y + 42 = 7
Subtract 42 from both sides

-15y + 42 - 42 = 7 - 42
Simplify

-15y = -35

Divide both sides by -15

-15/-15y = -35/-15

y = 7/3 or 2 1/3

Substitute value of y into one equation to solve for x

7x - 7/3 = 7
Add 7/3 to both sides to isolate variable

7x -7/3 + 7/3 = 7 + 7/3
Simplify

7x = 28/3
Divide both sides by 7 to solve for x
Remember when you divide fractions you flip the divisor and multiply

7/7 x = 28/3 * 1/7

x = 4/3 or 1 1/3
7x - y = 7 x + 2y = 6-example-1
User Tauquir
by
6.7k points