Question

When solving the system x + 2y = 9 and x - y = 6, which expression could be substituted for x in the first equation?

Answer 1

solve for x in the 2nd equation
x = 6+y

Answer 2

How do you solve it though?

Answer 3

x - y = 6 add y to both sides
x = 6-y

Answer 4

sorry x = 6+y

Answer 5

x + 2y = 9
and
x -y = 6, so
x = y + 6
substitute that for x int he first equation
x + 2y = 9
(y + 6) + 2y = 9
3y + 6 = 9
3y = 3
y = 1

Answer 6

x + 2y = 9 => x = 9 - 2y
x - y = 6 => x = 6 + y

x = x

9 - 2y = 6 + y
9-6 = y + 2y
3 = 3y
3/3 = y
1 = y
7 = x

Answer 7

So the correct point is (x,y) = (7,1)