The answer to this is C. 72
Answer:
see the explanation
Step-by-step explanation:
Let
A (1,6)------> location Brianna's house on a map
B (5,3)------> location Jordan's house on a map
we know that
One possible path from Brianna's house to Jordan's house it's a straight line ( the shortest distance)
using a graph tool
see the attached figure
<em>Find the distance points AB</em>
the formula to calculate the distance between two points is equal to

substitute the values




The distance from Brianna's house to Jordan's house is 5 units
It C. and if you need the equation for the area of a parallelogram its A=BH
Multiply both sides of the second equation by 100 to get rid of the decimals:
0.05<em>n</em> + 0.10<em>d</em> = 1.50
==> 5<em>n</em> + 10<em>d</em> = 150
Multiply both sides of the first equation by -5:
<em>n</em> + <em>d</em> = 21
==> -5<em>n</em> - 5<em>d</em> = -105
Add the two equations together:
(5<em>n</em> + 10<em>d</em>) + (-5<em>n</em> - 5<em>d</em>) = 150 + (-105)
Notice that the terms containing <em>n</em> get eliminated and we can solve for <em>d</em> :
(5<em>n</em> - 5<em>n</em>) + (10<em>d</em> - 5<em>d</em>) = 150 - 105
5<em>d</em> = 45
<em>d</em> = 45/5 = 9
Plug this into either original equation to solve for <em>n</em>. Doing this with the first equation is easiest:
<em>n</em> + 9 = 21
<em>n</em> = 21 - 9 = 12
So Donna used 12 nickels and 9 dimes.