Rearrange the first equation2x + y = 20take away 2x from both sidesy = 20 - 2x substitute this y value into the second equation6x - 5(20 - 2x) = 126x -100 +10x = 12add 100 to both sides6x + 10x = 11216x = 112divide both sides by 16 x = 7Substitute this x value into the first equation to get y.2(7) + y = 2014 + y = 20take away 14 from both sidesy = 6
So, y = 6 and x = 7
Answer:

Step-by-step explanation:
Apply these rules to solve:
• Angles on a straight line add up to 180 degrees.
• Angles in a triangle add up to 180 degrees.
• Opposite angles in a parallelogram are equal.
• Angles in a quadrilateral add up to 360 degrees.
3x^2 + 3y^2 = 75
Dividing through by 3 we get
x^2 + y^2 = 25
The center is at (0,0) answer
19.) 14/18, 21/27
20.) 3/21, 2/14
21.) 6
22.)8/9
25.) 36/73
26.) 1/3=.33 2/8=.25 Eric is more successful