2x^4
13b-10
5y+10
5a^3
2b^2+8a
We can use ratios and the cross-multiply-divide to find this.
The ratio 21:5 is avaliable via the question. We then need to compare that to the ratio x:100, the 100 being the percent and the x being the number of airplane parts.
21/5 = x/100
We can then solve for x to find the number of airplane parts. First we multiply by 100 on both sides to get 2100/5 = x. Therefore x = 420 and there are 420 airplane parts.
The answer is D because you can multiply the second equation by -4
Answer:
Option B. 
Step-by-step explanation:
we know that
The area of a circle is equal to

we have

substitute

Remember that
radians subtends the complete circle of area 
so
by proportion
Find the area of the related sector for a central angle of
radians
Let
x------> the area of the related sector

Answer:
y = 4/3x - 12
Step-by-step explanation:
To find the slope of the line, we do (y2 - y1) / (x2 - x1)
If we put in the values, we'll get
(-4 - -8) / (6 - 3)
Simplify and get
(-4 + 8) / 3
4 / 3
Your slope is now 4/3, so you can put it into your equation y = mx + b
y = 4/3x + b
To find b, we can plug in the values from one of your points. Lets use (3, -8)
-8 = 4/3 * 3 + b
Now solve the equation
-8 = 4 + b
-12 = b
Now that you have b, your equation is complete:
y = 4/3x - 12