Find startfraction partial derivative f over partial derivative x endfraction and startfraction partial derivative f over partial derivative y endfraction for the following function. f(x, y)equalsleft parenthesis 7 x minus 4 y right parenthesis superscript 9 s

Aproduction manager test 10 toothbrushes and finds that their mean lifetime is 450 hours. she then design sales package of this type of toothbrush. it states that the customers can expect the toothbrush to last approximately 460 hours. this is an example of what phase of inferential statistics

Measure of angles 31 (x+4) (3x+9) me

Peter measures the angles in a triangle. he finds that the angles are 95, 10 and 75. is he correct? explain your answer