Deirde spent 40% of her money in one shop and 35% of it in another. if she had €26.80 left, how much she at first

107.20 euros.

Step-by-step explanation:

Let the amount she had initially be x euros.

Then we have the equation:

x - 0.40x - 0.35x =  26.80

x - 0.75x = 26.80

0.25x = 25.80

Multiply both sides by 4:-

x = 107.20 euros.

Deirde had $ 107.2 at first

so if you add the 40% and the 35% together you would have 25% unused since its 25% you can just times it by four and you will get the total of $ 107.2

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.