Answer:
There are 24 nickels
Step-by-step explanation:
Let x represent the number of nickels
Let y represent the number of quarters
—————————————————————
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
—————————————————————
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.
————————————————————
Substitute in y = 28 - x
y = 28 - (24)
y = 4
The number of quarters is 4.
————————————————————
Checking:
24 nickels is $1.20 and 4 quarters is $1.00
That’s 28 coins.
Indeed $1.20 + $1.00 = $2.20
————————————————————
Answer:
B. sine; 46.5 feet high
Step-by-step explanation:
In this case, we use trigonometric ratio.
Assuming the horizontal ground, the cable and the height of the cliff forms a triangle,
The cable is the hypotenuse, the height of the cliff is opposite to the angle formed by the cable and the horizontal ground.
Thus; the most appropriate function is sine
Such that;
Sine θ = Opposite/Hypotenuse
Where; θ = 25°, opposite is the height of the cliff and hypotenuse is the cable, 110 ft
Therefore;
Sine 25° = Opp/ 110
Hence;
Opp = 110 ft × sine 25°
= 46.488 ft
= 46.5 ft
Therefore;
The function is Sine, and the height of the cliff is 46.5 ft high
Answer:
Compare the given equation of the circle (x - 1)² + (y -2)² = 2²
with standard form of circle: (x - h)² + (y - k)² = r²
Here, (h, k) is the center of the circle
and r is the radius of the circle.
Thus, The center of the circle is: (1, 2)
Also, for finding the point of intersections of (x - 1)² + (y -2)² = 2² and y = 2x + 2,
Substitute the value of y from equation of line in the equation of circle.
(x - 1)² + (2x + 2 - 2)² = 2²
⇒ (x - 1)² + (2x)² = 2²
⇒ x² + 1 - 2x + 4x² = 4
⇒ 5x² - 2x - 3 = 0
Applying Middle term splitting method
5x² - 5x + 3x - 3 = 0
⇒ 5x(x - 1) + 3(x - 1) = 0
⇒ (5x + 3)(x - 1) = 0
⇒ x = 
and x = 1
Thus, we get coordinates: 
and (1, 4)
The centroid divides the median into a 2:1 ratio. So, 9x-9=4x+16. We solve and get x=5. Therefore, OB is 36, and BE is half, 18.
Answer:
There is a pattern with the ratios of corresponding sides. You can see that the measurement of each side of the first triangle divided by two is the measure of the corresponding side of the second triangle. Use patterns like this to problem solve the length of missing sides of similar triangles.
