Part A:
Express the given number of hours and velocities of the cyclist as ordered pairs. The time (number of hours) can be our abscissa (x-coordinate) and the velocities can be our ordinate (y-coordinate). The coordinates are therefore (2, 18) and (4, 4). The equation that can be formed in this is established through the two-point equation.
(y - y₁) = ((y₂ - y₁)/(x₂ - x₁))(x - x₁)
Substitute the known variables.
(y - 18) = ((4 - 18)/(4 - 2))(x - 2)
Simplifying the equation,
y - 18 = -7(x - 2)
y = -7x + 32
<em>ANSWER: y = -7x + 32
</em>Part B: This can be graph in the Cartesian plane and numbers 1 to 8 can be substituted to y and take note of the ordered pairs for each point. The slope of the line should be -7 and the y-intercept is 32.<em>
</em>
We know that:
There is also an interesting property that relates the sine and the cosine of an angle:
We can find the cosine of theta using this equation:
![\begin{gathered} \cos ^2(\theta_1)=1-\sin ^2(\theta_1) \\ \cos (\theta_1)=\sqrt{1-\sin^2(\theta_1)} \\ \cos (\theta_1)=\sqrt[]{1-(-\frac{12}{13})^2} \\ \lvert\cos (\theta_1)\rvert=\sqrt[]{1-\frac{144}{169}}=\sqrt[]{\frac{25}{169}} \\ \lvert\cos (\theta_1)\rvert=\frac{5}{13} \end{gathered}](https://tex.z-dn.net/?f=%5Cbegin%7Bgathered%7D%20%5Ccos%20%5E2%28%5Ctheta_1%29%3D1-%5Csin%20%5E2%28%5Ctheta_1%29%20%5C%5C%20%5Ccos%20%28%5Ctheta_1%29%3D%5Csqrt%7B1-%5Csin%5E2%28%5Ctheta_1%29%7D%20%5C%5C%20%5Ccos%20%28%5Ctheta_1%29%3D%5Csqrt%5B%5D%7B1-%28-%5Cfrac%7B12%7D%7B13%7D%29%5E2%7D%20%5C%5C%20%5Clvert%5Ccos%20%28%5Ctheta_1%29%5Crvert%3D%5Csqrt%5B%5D%7B1-%5Cfrac%7B144%7D%7B169%7D%7D%3D%5Csqrt%5B%5D%7B%5Cfrac%7B25%7D%7B169%7D%7D%20%5C%5C%20%5Clvert%5Ccos%20%28%5Ctheta_1%29%5Crvert%3D%5Cfrac%7B5%7D%7B13%7D%20%5Cend%7Bgathered%7D)
Since theta is in the third quadrant then its cosine must be a negative number so:
Answer:
-4x³ - 8y - 1
General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
<u>Algebra I</u>
Step-by-step explanation:
<u>Step 1: Define</u>
<em>Identify</em>
7 - 6y - 5x³ - 1 + x³ - 7 - 2y
<u>Step 2: Simplify</u>
- [Addition] Combine like terms (x³): -4x³ + 7 - 6y - 1 - 7 - 2y
- [Subtraction] Combine like terms (y): -4x³ - 8y + 7 - 1 - 7
- [Subtraction] Combine like terms: -4x³ - 8y - 1
Plug in 50
-6(50) + 150
-300 + 150 = -150
The solution is -150
We want to get out x's together on the right side of the inequality.
So, subtract <em>x </em>from both sides to get 9 < 3x.
Now divide both sides by 3 and we get 3 < x.
I personally like to have my variables on the left so we can move the 3 to the left and the <em>x</em> to the right but if we do that, we have to switch the inequality sign.
So we can rewrite this as x > 3.
