Multiplication, addition, subtraction
√z = 13 - 8
√z = 5
z = 5²
z = 25
In this case the z can be any number, however z cannot be less than 0 and that is the restriction. (for example; √-1 = irrational number, cannot be solved.)
U basically solve: (4sqrt8)*2 + (5 sqrt 12 + 6 sqrt 20)*2
X-y=2 (*-2) --> -2x+2y=-4
2x+3y=14
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2x+3y=14
-2x+2y=-4
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5y=10
y=2