A quadratic function is one of the form f(x) = ax2 + bx + c, where a, b, and c are numbers with a not equal to zero. The graph of a quadratic function is a curve called a parabola. A parabola intersects its axis of symmetry at a point called the vertex of the parabola. You know that two points determine a line.
Hope it helps!
Answer: It’s A
Step-by-step explanation: C= -14/3 which is simplified to -4 2/3
It looks like you're asked to find the value of y(-1) given its implicit derivative,
and with initial condition y(2) = -1.
The differential equation is separable:
Integrate both sides:
Solve for y :
![y = -\dfrac1{\sqrt[3]{3x+C}}](https://tex.z-dn.net/?f=y%20%3D%20-%5Cdfrac1%7B%5Csqrt%5B3%5D%7B3x%2BC%7D%7D)
Use the initial condition to solve for C :
![y(2) = -1 \implies -1 = -\dfrac1{\sqrt[3]{3\times2+C}} \implies C = -5](https://tex.z-dn.net/?f=y%282%29%20%3D%20-1%20%5Cimplies%20-1%20%3D%20-%5Cdfrac1%7B%5Csqrt%5B3%5D%7B3%5Ctimes2%2BC%7D%7D%20%5Cimplies%20C%20%3D%20-5)
Then the particular solution to the differential equation is
![y(x) = -\dfrac1{\sqrt[3]{3x-5}}](https://tex.z-dn.net/?f=y%28x%29%20%3D%20-%5Cdfrac1%7B%5Csqrt%5B3%5D%7B3x-5%7D%7D)
and so
![y(-1) = -\dfrac1{\sqrt[3]{3\times(-1)-5}} = \boxed{\dfrac12}](https://tex.z-dn.net/?f=y%28-1%29%20%3D%20-%5Cdfrac1%7B%5Csqrt%5B3%5D%7B3%5Ctimes%28-1%29-5%7D%7D%20%3D%20%5Cboxed%7B%5Cdfrac12%7D)
39. 13x3.....................
18 kg of 15% copper and 72 kg of 60% copper should be combined by the metalworker to create 90 kg of 51% copper alloy.
<u>Step-by-step explanation:</u>
Let x = kg of 15% copper alloy
Let y = kg of 60% copper alloy
Since we need to create 90 kg of alloy we know:
x + y = 90
51% of 90 kg = 45.9 kg of copper
So we're interested in creating 45.9 kg of copper
We need some amount of 15% copper and some amount of 60% copper to create 45.9 kg of copper:
0.15x + 0.60y = 45.9
but
x + y = 90
x= 90 - y
substituting that value in for x
0.15(90 - y) + 0.60y = 45.9
13.5 - 0.15y + 0.60y = 45.9
0.45y = 32.4
y = 72
Substituting this y value to solve for x gives:
x + y = 90
x= 90-72
x=18
Therefore, in order to create 90kg of 51% alloy, we'd need 18 kg of 15% copper and 72 kg of 60% copper.
