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If five times a certain integer is subtracted from the square of the integer, the integer is 63, find the integer |
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Answer» Step-by-step EXPLANATION: LET the number be X Five times a number 5X Twice the X^2 =2X^2 2X^2-5X =63 2X^2-5X -63=0 a=2 b= -5 c= -63 X =[ 5+ — (25 -4×2×-’63)] / 2×2 =[5+ —(529)^1/2] /4 [Note : (529)^1/2 =23] X1=(5+23)/4 =7 X2 =(5 -23)/4 = -18/4 not integer The number is 7 Verification 2X^2= 2×49=98 5×X =5×7=35 Diffrence is 98-35= 63 |
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