Solve this pair of simultaneous equations.
5x + 2y = 20
x + 4y = 13
X=
y=

y= 2.5

x= 3

Step-by-step explanation:

multiply eqn 2 by 5

5x +20y =65

eqn 2 -1

20-2)y=65-20

18y=45

y=2.5

x+4×2.5 =13

x+10=13

x=3

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: