If the gradient of a line, C, is 2/3, what is the gradient of a line which perpendicular to C

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Step-by-step explanation:

answer: 4  

the square root of 16 is 4. it is a very simple mathematic concept. a square root when a number multiplied by itself will result in a number. here, the number 16 comes when 4 is multiplied by 4. hence the square root of 16 is 4. you can always figure out a square root by the inverse operation of squaring.  

$25 becasue a 10 increase would make it from 80 to 50