I believe the equation would be 765 -8t = 421. Then you would solve for t and get 43 seconds. I hope this helps!! :)
The expression with a rational exponent of the seventh root of x to the third power is x to the three sevenths power ⇒ answer A
Step-by-step explanation:
Let us explain how to change the radical expression as an expression
with a rational exponent
1. Find the number of the root and make it the denominator of the
fraction exponent
2. Find the power of the term under the radical and make it the
numerator of the fraction exponent
Examples:

![\sqrt[3]{x^{n}}=x^{\frac{n}{3}}](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7Bx%5E%7Bn%7D%7D%3Dx%5E%7B%5Cfrac%7Bn%7D%7B3%7D%7D)
![\sqrt[5]{x^{n}}=x^{\frac{n}{5}}](https://tex.z-dn.net/?f=%5Csqrt%5B5%5D%7Bx%5E%7Bn%7D%7D%3Dx%5E%7B%5Cfrac%7Bn%7D%7B5%7D%7D)
So ![\sqrt[m]{x^{n}}=x^{\frac{n}{m}}](https://tex.z-dn.net/?f=%5Csqrt%5Bm%5D%7Bx%5E%7Bn%7D%7D%3Dx%5E%7B%5Cfrac%7Bn%7D%7Bm%7D%7D)
∵ the radical expression is the seventh root of x to the third power
∵ seventh root = ![\sqrt[7]{}](https://tex.z-dn.net/?f=%5Csqrt%5B7%5D%7B%7D)
∵ x to the third power = x³
∴ seventh root of x to the third power = ![\sqrt[7]{x^{3}}](https://tex.z-dn.net/?f=%5Csqrt%5B7%5D%7Bx%5E%7B3%7D%7D)
Let us change it to the rational exponent
∵ ![\sqrt[m]{x^{n}}=x^{\frac{n}{m}}](https://tex.z-dn.net/?f=%5Csqrt%5Bm%5D%7Bx%5E%7Bn%7D%7D%3Dx%5E%7B%5Cfrac%7Bn%7D%7Bm%7D%7D)
∵ ![\sqrt[7]{x^{3}}](https://tex.z-dn.net/?f=%5Csqrt%5B7%5D%7Bx%5E%7B3%7D%7D)
∴ m = 7 and n = 3
∴
= 
∵
is x to the three sevenths power
∴
is x to the three sevenths power
The expression with a rational exponent of the seventh root of x to the third power is x to the three sevenths power
Learn more:
You can learn more about radical equation is brainly.com/question/7153188
#LearnwithBrainly
That is about right... 2,514 X 2 = 5,028 so he is about 1,000 off. I will leave the rest to you.
M < PQS + m < RQS = 180° because they are supplementary angles.
Therefore:
(3x + 3) + (x + 19) = 180
3x — 3 + x + 19 = 180
4x + 16 = 180
Subtract 16 from both sides
4x — 16 = 180 — 16
4x = 164
Divide both sides by 4:
4x/4 = 164/4
x = 41
Therefore, the correct answer is x = 41