2 + 4 + 6 + 8 + ... + 2x = 210
=> 2.(1 + 2 + 3 + 4 + ... + x) = 210
=> 2.(1 + x).x:2 = 210
=> (1 + x).x = 210 = 15.14
=> x = 14
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2 + 4 + 6 + 8 + ... + 2x = 210
=> 2.(1 + 2 + 3 + 4 + ... + x) = 210
=> 2.(1 + x).x:2 = 210
=> (1 + x).x = 210 = 15.14
=> x = 14
2+4+6+8+....+2x =210
2+4+6+8...+2x = 210
2+4+6+8+.....+2x=210
2+4+6+8+...+2x=210
2+4+6+8+.........+2x=210
2+4+6+8+.........+2x=210
2+4+6+8+...+2x=210
2+4+6+8+...+2x=210
2+4+6+8+...........+2x=210