The points (2,r) and (5,-1) lie on a line with slope 4. what is r

R=-13

Step-by-step explanation:

S=-1-r/5-2

4=-1-r/3

Cross multiply

4*3=-1-r

12=-1-r

Collect like terms

12+1=-r

-r=13

Divide both sides by -

r=-13

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.

it would open into a square depending on the type of envelope i’m not sure about the second part