Answer:
There are 24 nickels
Step-by-step explanation:
Let x represent the number of nickels
Let y represent the number of quarters
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Value Value
Type Number of of
of of each all
Coin Coin Coin Coin
—————————————————————
Nickels | x | $0.05 | $0.05x
Quarters | y | $0.25 | $0.25y
—————————————————————
Totals 28 ——— $2.20
•••••••••••••••••••••••••••••••••••••••••••••••••
The first equation comes from the “Number of coins” column.
(Number of nickels) + (Number of quarters) = (total number of coins)
Equation: x + y = 28
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The second equation comes from the “value of all coins” column.
(Value of all nickels) + (Value of all quarters) = (Total value of all coins)
0.05x + 0.25y = 2.20
Remove the decimals by multiplying each term by 100:
5x + 25y = 220
—————————————————————
So we have the system of equations:
{x + y = 28
{5x + 25y = 202
Solve by substitution. Solve the first equation for y:
x + y = 28
y = 28 - x
Substitute (28 - x) for y in 5x + 25y = 220
5x + 25 (28 - x) = 220
5x + 700 - 25x = 220
-20x + 700 = 220
-20x = -480
x = 24
The number of nickels is 24.
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Substitute in y = 28 - x
y = 28 - (24)
y = 4
The number of quarters is 4.
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Checking:
24 nickels is $1.20 and 4 quarters is $1.00
That’s 28 coins.
Indeed $1.20 + $1.00 = $2.20
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Answer:C) -4a+22b because u add 12a ➕-16a and u get negative 4 then u mines 26b-4b and u get 22
Step-by-step explanation:
Answer:
90 Degrees.
The angle which is equal to its supplement is 90 degrees.
1. Change both numbers to common base.
2. Use quotient rule 
e)
You can write 9 as 3², then both numbers have the same base.
, where x is the exponent
I cannot really see the exponents because picture is bad quality.
You want to replace x and y with actual numbers, but as I said the picture is too bad.
f)
Convert to base 4, then quotient rule.
g)
Use the quotient rule, you already have same base.
h)
Convert to base 
, then quotient rule.
Take a look at the order of the letters of ur triangles.
ABC and PQR.....it says they are congruent....so they r equal.
And the order of the letters means : < A = < P, and < B = < Q, and < C = < R.
so if < B = < Q....set them equal to each other and solve for v
3v + 4 = 8v - 6
6 + 4 = 8v - 3v
10 = 5v
10/5 = v
2 = v
now we sub our 2 in for v
< B = 3v + 4......3(2) + 4 = 10
< Q = 8v - 6.......8(2) - 6 = 10
so < B and < Q both equal 10 <==
