First you need to eliminate one of the letters. In this case, by adding the two equations together we can eliminate y.
x - y = 90
+
x + y = 360
__________
2x = 450
x = 225
if x = 225 we can put this back in to the first equation to find y.
x - y = 90 ----- 225 - y = 90 ----- 225 - 90 = y ----- 135 = y
Now, knowing that x = 225 and y = 135 we can double check that this is right by trying these numbers in the second equation.
x + y = 360 ----- 225 + 135 = 360!! Correct!
Y=30
(200-90)+20=10
Answer 146 - 56 = 90 :)
Add everything up on the left side first: 52 + 90 + (-76) + x = 66 + x 66 + x = 360 Now just subtract 66 from both sides: 66 + x - 66 = 360 - 66 x = 294
90 + 90 + 60 = 240
What plus 11 equals -5?
Y=30
(200-90)+20=10
90
360
62
Answer 146 - 56 = 90 :)
Add everything up on the left side first: 52 + 90 + (-76) + x = 66 + x 66 + x = 360 Now just subtract 66 from both sides: 66 + x - 66 = 360 - 66 x = 294
90 + 90 + 60 = 240
x - 54 = 36x = 90
127 minus 90 equals 37. 127 - 90 = 37.
Easy, 360!