We consider general solution and the generalized Hyers-Ulam stability of an Euler-Lagrange quadratic functional equation <svg style="vertical-align:-3.56265pt;width:333.63751px;" id="M1" height="16.6625" version="1.1" viewBox="0 0 333.63751 16.6625" width="333.63751" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg"> <g transform="matrix(.017,-0,0,-.017,.062,12.162)"><path id="x1D453" d="M619 670q0 -13 -9 -26t-18 -19q-13 -10 -25 2q-36 38 -66 38q-31 0 -54.5 -50t-45.5 -185h120l-20 -31l-107 -12q-23 -138 -57 -293q-27 -122 -55 -184.5t-75 -109.5q-60 -61 -114 -61q-25 0 -47.5 15t-22.5 31q0 17 31 44q11 8 20 -1q10 -11 31 -19t35 -8q26 0 47 19
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transform="matrix(.017,-0,0,-.017,255.894,12.162)"><use xlink:href="#x1D465"/></g><g transform="matrix(.017,-0,0,-.017,265.396,12.162)"><use xlink:href="#x29"/></g><g transform="matrix(.017,-0,0,-.017,275.051,12.162)"><use xlink:href="#x2B"/></g><g transform="matrix(.017,-0,0,-.017,288.803,12.162)"><use xlink:href="#x1D460"/></g><g transform="matrix(.017,-0,0,-.017,295.178,12.162)"><use xlink:href="#x1D453"/></g><g transform="matrix(.017,-0,0,-.017,306.091,12.162)"><use xlink:href="#x28"/></g><g transform="matrix(.017,-0,0,-.017,311.973,12.162)"><use xlink:href="#x1D466"/></g><g transform="matrix(.017,-0,0,-.017,321.815,12.162)"><use xlink:href="#x29"/></g><g transform="matrix(.017,-0,0,-.017,327.696,12.162)"><path id="x5D" d="M226 -163h-170v27q79 7 94 20t15 73v627q0 59 -15 72t-94 20v27h170v-866z" /></g> </svg> in fuzzy Banach spaces, where <svg style="vertical-align:-0.1638pt;width:7.3000002px;" id="M2" height="7.9499998" version="1.1" viewBox="0 0 7.3000002 7.9499998" 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