Can someone tell me what i'm doing wrong? i think i know how to do quadratic formula, and i know all the steps, but the last step where you solve after everything is in it's place really confuses me. i put some pictures of what i did and what the question was.

*most answer will be the brainliest! **

step-by-step explanation:

one of the most important purposes of surface treatment is to alter surface properties according to the requirement of specific applications. for example, hydrophobic coating has been utilized on windshield and eyeglasses. gold atom monolayer on substrate has become a popular surface bioconjugation strategy.  

the correct answer would be:

220 centimeters

to get this you can use the pythagorean theorem

hope this

step-by-step explanation: