Answer:
y = - 3x - 7
Step-by-step explanation:
The equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept )
Here m = - 3, then
y = - 3x + c ← is the partial equation
To find c substitute (- 2, - 1) into the partial equation
- 1 = 6 + c ⇒ c = - 1 - 6 = - 7
y = - 3x - 7 ← equation of line
0.373 seconds. First, calculate the initial vertical velocity of the shell. 800sin(30) = 800*0.5 = 400 m/s Now the formula for the distance traveled is d = 400 m/s * T + 0.5A T^2 Substituting known values gives. 150 = 400 m/s * T + 0.5*9.80m/s^2 T^2 150 = 400 m/s * T + 4.9 m/s^2 T^2 Arrange as a quadratic formula 0 = 400 m/s * T + 4.9 m/s^2 T^2 - 150 4.9 m/s^2 T^2 + 400 m/s * T - 150 = 0 Now solve for T using the quadratic formula with a=4.9, b=400, and c=-150 The calculated value is 0.373 seconds. Is this value reasonable? Let's check. The initial downward velocity is 400 m/s. So 150/400 = 0.375 seconds. Since the actual time will be a bit less due to acceleration by gravity and since the total time is so short, there won't be much acceleration due to gravity, the value of 0.373 is quite reasonable.
This is the the concept of trigonometry, to get the sine value of the the function given we shall proceed as follows;
Using Pythagorean theorem, the hypotenuse of the triangle will be found as follows;
The side length will be 8 units since the y-coordinate is -8
The side width will be 3 units since the x- coordinate is 3
c^2=a^2+b^2
c^2=(3)^2+(-8)^2
c^2=9+64
c^2=73
c=sqrt(73)
Therefore the sine value will be:
sin x=3/sqrt(73)
multiply both numerator and denominator by sqrt(73) we get:
sin x=(3√73)/73
Therefore the answer is A]