(√2+√18)²/16=((√2)²+(√18)²)/16=(2+18)/16=20/16=1,25
(√7+√17)²/12+√119=(7+17)/12=2+√119
<span>√18-7x=x
</span>x+7x=√18
8x=√18
x=√
x=3√2//8
<span>
√4x+32/7=6
</span>2√x+32/7-6=0
2(√x+15/7-3)=0
√x+15/7-3=0
√x=3+15/7
√x=21/7+15/7
√x=36/7
x=1296/49
(3^-2*5^-3)÷15^-3=(1/3^2*1/5^3)÷1/15^3=
(1/9*1/125)÷1/3375=1/1125*3375=3
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13x-9x-15=53
4x-15=53
4x=15+53
4x=68
x=68:4
x=17