Respuesta :

mathwonder7
its D              does your work need to be shown?
dalendrk
[tex]\Delta ADC\sim\Delta CDB\\\\therefore\\\\\dfrac{21}{x}=\dfrac{x}{49}\ \ \ \ |cross\ multiply\\\\x\cdot x=21\cdot49\\\\x^2=21\cdot49\to x=\sqrt{21\cdot49}\\\\x=7\sqrt{21}\to x\approx32.1[/tex]

Answer: D. 32.1
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