X=4, y=28. 7x=2x+20, so subtract 2x from both sides and you’ll get 5x=20. Divide both sides by 5 and you’ll get x=4. Substitute this into the other equations and they will both equal 28.
The second one is the correct equation. The constant to the right should be the diameter squared, while the numbers inside the parentheses should be the opposite.
Answer:
89.1° or -1.4°
Step-by-step explanation:
1. Location:
You are on the Mont-Saint-Jean escarpment, near the Belgian town of Waterloo.
The French troops are about 50 m below you and 1.2 km distant.
2. Finding the firing angle
Data:
R = 1200 m
u = 600 m/s
h = -50 m (the height of the target)
a = 9.8 m/s²
We have two conditions.
Horizontal distance
(1) 1200 = 600t cosθ
Vertical distance
(2) -50 = 600t sinθ - 4.9t²
Divide each side of (1) by 600cosθ.

Substitute (3) into (2)

Recall that
(5) sec²θ = 1/cos²θ = tan²θ + 1
Substitute (5) into (4)

Set up a quadratic equation

Solve for θ
Use the quadratic formula.
tanθ = 61.249 or -0.025
θ = arctan(61.249) = 89.1° or
θ = arctan(-0.025) = -1.4°
Answer:
822
Step-by-step explanation:
Answer:
7 each
Step-by-step explanation:
28÷4=7
1/4 of 28=7