50 1.) find the value of the expression 5x2–(3xy–7x2)+(5xy–12x2) when x=−0.25 and y=45x2–(3xy–7x2)+(5xy–12x2) when x=−5 and y=0.12.) what binomial do you have to add to the polynomial x2+y2–2xy+1 to get a polynomial: not containing the variable x2.a) what binomial do you have to add to the polynomial x2+y2–2xy+1 to get a polynomial: not containing the variable y?

1. The expression simplifies to ...

... = 5x² -3xy +7x² +5xy -12x²

... = (5+7-12)x² +(-3+5)xy

... = 2xy

1a. for (x, y) = (-0.25, 4), -2xy = -2

1b. for (x, y) = (-5, 0.1), -2xy = -1

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2. To eliminate the terms you don't want, add their opposite.

2a. The terms you don't want are x²-2xy. To get rid of them, add the opposite of this sum: 2xy -x².

2b. The terms you don't want are y²-2xy. Add their opposite: 2xy-y².

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Comment on point value

Last time I checked, 5 (or 8) and 50 were very different things.

solution:

the given function is ,

      =

the three roots of this quadratic function is , 0 ,8 and 10.all the roots are real and rational.

if a quadratic equation is of the form ,

sum of the roots = a + b +c= 0+8+10=18=  

product of roots taken two at a time = a b + b c+ c a = 0+80+0=80 =  

product of roots = a b c = 0=  

there are 11 doors in a hall starting from 0 to 11.the entry in the hall is permitted through gate number 0 and exit is allowed through only gate number 8 and 10.so, three roots(0,8,10) of quadratic function is given by entry and exit route of this hall.

a

step-by-step explanation: