Here are some equations that are true when x=3 and y=4 but there is at least one mistake. Click on the ticks and crosses to show this piece of work correctly marked.
x + y = 7 
x  y = 1 
y  x = 1 
2x + 3y = 18 
5x  2y = 7 
4y  x = 19 
xy  10 = 2 
180  2x + y = 186 
20x  3xy = 24 
x^{2} + y = 23 
10x  y^{2} = 14 
y^{2}  x^{2} = 7 
x^{2}y + 13 = 49 
x^{2}y^{2}  2x = 152 
x^{2}y^{3} = 576 
x! + y = 10 
5(x + y) = 52 
3y Ã· x = 4 
xy
2
= 6

84
xy
= 7

15y
5x
= y



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