When (2x-20)+86=0
2x-20=-86
2x=-46
x=-23
Answer:
78 nickels and 22 dimes
Step-by-step explanation:
Nickels = n, Dimes = d
<u>Number of coins = 100</u>
<u>Total sum in the piggy bank = $6.60 </u>
<u>Consider the first equation in the second:</u>
- 5(100 -d) + 10d = 660
- 500 - 5d + 10d = 660
- 5d = 110
- d = 110/5
- d = 22
- n = 100 - 22
- n = 78
<u>Answer:</u> nickels 78 and dimes 22
A is the answer i think so
I think 7x-y=-2 is the answer
Answer:
144°
Step-by-step explanation:
step 1
Find the measure of the central angle of the regular pentagon
Divide 360 degrees by 5 (the number of sides)

Let
c----> the center of the pentagon
we know that
m∠ECA=72°
m∠ACB=72°
therefore
m∠ECB=m∠ECA+m∠ACB
substitute the values
m∠ECB=72°+72°=144°
The measure of angle ECB is equal to the degrees that the pentagon rotate