Answer:
Sine, cosine and tangent
Step-by-step explanation:
Given a right triangle you can find the sine (or cosine, or tangent) of either of the non- 90° angles.
Let X = the number of pennies.
The number of nickels would be 2X
A penny is 0.01 and a nickel is 0.05
Now you have:
0.01x + 2(0.05x) = 8.80
Simplify:
0.01x + 0.10x = 8.80
Combine like terms:
0.11x = 8.80
Divide both sides by 0.11:
x = 8.80 / 0.11
x = 80
Pennies = X = 80 total pennies.
Nickels = 2x = 2 *80 = 160 nickels.
6x-2y=2
-3x+4y=5
2(-3x)+2(4y)=2(5)
-6x+8y=10
6x-2y=2
-6x+8y=10
6y=12
y=2
6x-2(2)=2
6x-4=2
6x=6
x=1
y=2 and x=1
Answer:
A. 25 girls
Step-by-step explanation:
Suppose the number of boys is b and the number of girls is g.
We know that the ratio of boys to girls is 6 to 5, so we can write this as:
b:g = 6:5 or b/g = 6/5
We also know that there are 30 boys, so b = 30. We plug this value of 30 in for b in our ratio. Now, we just have a proportion with one variable g:
⇒ 
Cross-multiplying, we get:
6 * g = 30 * 5 = 150
g = 150/6 = 25
Thus, there are 25 girls, so the answer is A.
Hope this helps!