X x 3,15 + X x 12,69 = 98,208
X x ( 3,15 + 12,69 ) = 98,208
X x 15,84 = 98,208
X = 98,208 : 15,84
X = 6,2
a ) X x 3,15 + X x 12,69 = 98,208
X x ( 3,15 + 12,69 ) = 98,208
X x 15,84 = 98,208
X = 98,208 : 15,84
X = 6,2
b ) X : 18,3 - 22,54 = 6,74
X : 18,3 = 6,74 + 22,54
X : 18,3 = 29,28
X = 29,28 x 18,3
X = 535,824
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