Area of rectangle:

Area is 21 square units. The Width of rectangle is 5 less than 4 times the length. Find the Dimension.

Write the formula and answer MUST SHOW ALL WORK!

its 7 for width and 3 and length

Step-by-step explanation:

L * W = 21

W= 4L-5

find the factors for 21 which is 21 and 1 or 7 and 3. Plug in which one is valified. 7 and 3 are correct.

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.