Answer:
n = 6 + 
or n = 6 -
Step-by-step explanation:
We can solve this equation using the quadratic formula OR Completing the Square method.
n² + 14 = 12n
rearrange : n² - 12n + 14 = 0
here a= 1 , b = -12, c = 14
the quadratic formula says: x = - b/ (2a) + root(b^2 - 4ac) / (2a)
or x = - b/ (2a) - root(b^2 - 4ac) / (2a)
x = - (-12)/ (2) + root((-12)^2 - 4*14) / (2)
x = 6 + root (144 - 56) / 2
x = 6 + root(88)/2
x = 6 + root(4*22) / 2
x = 6 + 2*root(22)/2
x = 6 + root(22) = 6 +
so x =6 + or x = 6 -
In this case x = n
n = 6 + or n = 6 -
length (l) =54
breath (b) =72
l²+b²= diagonal²..........(Pythagoras theorem) and (all sides of rectangle are 90degree)
(54)²+(72)²=diagonal²
2916+5184=diagonal²
8100=diagonal²
90= diagonal.............(taking square root)
length of diagonal is 90ft
i hope it helps
have a nice day and thanks for asking this question
Answer:
24 quarters and 49 nickels
Step-by-step explanation:
This situation has two unknowns - the total number of nickels and the total number of quarters. Because we have two unknowns, we will write a system of equations with two equations using the two unknowns.
- n+q=73 is an equation representing the total number of coins
- 0.05n+0.25q=8.45 is an equation representing the total value in money based on the number of coin. 0.05 and 0.25 come from the value of a nickel and quarter individually.
We write the first equation in terms of q by subtracting it across the equal sign to get n=73-q. We now substitute this for n in the second equation.
0.05(73-q)+0.25q=8.45
3.65-0.05q+0.25q=8.45
3.65+0.20q=8.45
After simplifying, we subtract 3.65 across and divide by the coefficient of q.
0.20q=4.8
q=24
We now know of the 73 coins that 24 are quarters. To find the number of nickels, we subtract 24 from 73 and get 49 nickels.
It has to do with the number of dimensions you have in the figure. For example, in a square you have 2 dimensions, length and width. Since you have only two you use units^2. In a cube, you have 3 dimensions, length, width and height, which is where you get the units^3.
