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.
42 divided by 7 =6 then u times 5 and 6 together . Then times 2 by 6 together so the answer is 30:12
<span>A midpoint divides a line or a segment into two equal parts. If D is the midpoint of the segment AC and C is the midpoint of segment DB, what is the length of the segment AB, if AC = 3 cm.</span>
If D is the midpoint of AC, then AD=DC
If C is the midpoint of DB, then DC=CB
If AC=3cm. then then DC-3/2=1.5
If DC=1.5 then CB is 1.5 also
AB=AC+CB
AB=3+1.5
AB=4.5
Answer: Nick must now at least 6 yards.
Step-by-step explanation:
Since Nick has $80 saved already, and he makes $40 per yard that he mows, thus can be put up in an equation as:
= 80 + 40y
where y = number of yards
Since Nick needs to raise at least $320 for his trip, the equation to solve this will be:
80 + 40x ≥ 320
40x ≥ 320 - 80
40x ≥ 240
x ≥ 240/40
x ≥ 6
Therefore, Nick must now at least 6 yards.
Answer:

Step-by-step explanation:
Let the equation of the perpendicular line is,
y = mx + b
where m = slope of the line
b = y-intercept
From the graph, slope of the line passing through (0, -1) and (3, 1),
m' =
m' = 
m' = 
To get the slope (m) of this line we will use the property of perpendicular lines,
m × m' = (-1)
m ×
= -1
m = 
Equation of the perpendicular line will be,

x-intercept of the line is (-3) therefore, point on the line is (-3, 0)
0 = 
b = 
Equation of the line will be,
