How do you solve this system of equations: 2xy=11and2x9y=3?

1 Answer
Dec 3, 2017

x=6
y=1

Explanation:

Solve both equations for 2x and set them equal to each other.

2xy=11
so 2x=11+y

2x9y=3
so 2x=3+9y

Because both of the equations are equal to 2x, they are equal ro each other.

11+y=2x   and   2x=3+9y

11+y=3+9y

1) Subtract y from both sides to get all the y's together

11=3+8y

2) Subtract 3 from both sides to isolate the 8y term

8=8y

3) Divide both sides by 8 to isolate y
1=y answer for y
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

To find x, sub in 1 for y and solve for x

2xy=11
2x1=11

1) Add 1 to both sides to isolate the 2x term
2x=12

2) Divide both sides by 2 to isolate x
x=6 answer for x

Answer:
x=6
y=1
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Check
Sub in the values for x and y back into the original equations.

(1) 2x9y=3

(2)(6)(9)(1) is supposed to equal 3

129 is supposed to equal 3

3 does equal 3   ✓
..................................

(2) 2xy=11

(2)(6)1 is supposed to equal 11

121 is supposed to equal 11

11 does equal 11   ✓