I cannot see Zoe's work to explain the error, but the correct method of solving is listed:
x is the number of 30-second ads
y is the number of 60-second ads
x+y=12(60)=720 would be the first equation; this is because while the ads together make 12 minutes, the ad times are in seconds. This means we must multiply 12 by 60.
y=2x is the second equation
Our system is then
x+y=720
y=2x
We will use substitution to solve this. Plug 2x in place of y in the first equation:
x+2x = 720
Combine like terms:
3x = 720
Divide both sides by 3:
3x/3 = 720/3
x = 240
Substitute this value in for x in the second equation:
y=2(240)
y=480
x=6x-2 This would be your answer, hope this helps if you need any further explanation feel free to let me know and I would be happy to help you out.
Answer:
I just took the test, it's 1 and 3
Step-by-step explanation:
Answer:
<em>c=6, d=2</em>
Step-by-step explanation:
<em>Equations
</em>
We must find the values of c and d that make the below equation be true
![\sqrt[3]{162x^cy^5}=3x^2y \sqrt[3]{6y^d}](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7B162x%5Ecy%5E5%7D%3D3x%5E2y%20%5Csqrt%5B3%5D%7B6y%5Ed%7D)
Let's cube both sides of the equation:
![\left (\sqrt[3]{162x^cy^5}\right )^3=\left (3x^2y \sqrt[3]{6y^d}\right)^3](https://tex.z-dn.net/?f=%5Cleft%20%28%5Csqrt%5B3%5D%7B162x%5Ecy%5E5%7D%5Cright%20%29%5E3%3D%5Cleft%20%283x%5E2y%20%5Csqrt%5B3%5D%7B6y%5Ed%7D%5Cright%29%5E3)
The left side just simplifies the cubic root with the cube:
![162x^cy^5=\left (3x^2y \sqrt[3]{6y^d}\right)^3](https://tex.z-dn.net/?f=162x%5Ecy%5E5%3D%5Cleft%20%283x%5E2y%20%5Csqrt%5B3%5D%7B6y%5Ed%7D%5Cright%29%5E3)
On the right side, we'll simplify the cubic root where possible and power what's outside of the root:
Simplifying
Equating the powers of x and y separately we find
c=6
5=3+d
d=2
The values are
