Answer:
you got this your smart
Step-by-step explanation:
A² = c² - b²
a² = 21² - 13 ²
a² = 441 - 169
a² = 272
a = √272 = 16.49242 ≈ 16.49
Answer : D ) 16.49
This response is based upon your having had some background in calculus. "dx" is not introduced before that.
Take a look at the sample function y = f(x) = x^2 + 9. Here x is the independent variable; the dependent variable y changes with x.
Now, for a big jump: we consider finding the area under a curve (graph) between x = a and x = b. We subdivide that interval [a,b] into n vertical slices of area. Each of those slices has its own area: f(x)*dx, where dx represents the width of such subarea. f(x)*dx is the actual subarea. To find the total area under the curve f(x) between x= a and x = b, we add up all of these individual subareas between x = a and x = b. Note that the subinterval width is
b-a
dx = ---------- , and that dx becomes smaller and smaller as the number of
n subintervals increases.
Once again, this all makes sense only if you've begun calculus (particularly integral calculus). Do not try to relate it to earlier math courses.
Step-by-step explanation:
![f(x)=x^2,\ g(x)=x+6,\ h(x)=7\\\\h(x)=7\ \text{It's the constant function. Therefore}\ h\{g[f(x)]\}=7](https://tex.z-dn.net/?f=f%28x%29%3Dx%5E2%2C%5C%20g%28x%29%3Dx%2B6%2C%5C%20h%28x%29%3D7%5C%5C%5C%5Ch%28x%29%3D7%5C%20%5Ctext%7BIt%27s%20the%20constant%20function.%20Therefore%7D%5C%20h%5C%7Bg%5Bf%28x%29%5D%5C%7D%3D7)
