The distance of the ship from the shore is given by:
tan θ=opposite/adjacent
θ=28°
adjacent=x
opposite=360 m
substituting the values in our equation we get:
tan 28=360/x
solving for x we get
x=360/tan 28
x=677.06 m
We label each equation
3x + 4y = 5 (1)
2x – 3y = 9 (2)
We now want to get rid of one of the variables (x or y). Lets get rid of x:
We need (1) and (2) to have the same number of x's so we multiple (1) by 2 and (2) by 3 so they both have 6 x's
6x + 8y = 10 (1)*2
6x - 9y = 27 (2)*3
Now to get rid of the x's we take one of the equations from the other. It is easier to do (2)*3 -(1)*2
6x - 9y = 27 (2)*3
6x + 8y = 10 (1)*2
-17y = 17
If we devide this equation by -17 we get
y = -1
We can plug this value of y into (1) to get
3x -4 = 5
add 4 to both sides of the equation
3x = 9
Divide by 3
x = 3
Now to check put x and y into (2)
6 - (-3) = 9
As this is true, we have the solution
x = 3, y = -1
7x^2 -10x +3 = 0
Use the quadratic formula
a = 7 b = -10 c=3
x= [--10 +-sq rt(100 - 4*7*3)] / 2*7
x= [--10 +-sq rt(100 - 84)] / 14
x= [10 +-4] / 14
x1 = 14/14 = 1
x2 = ([6] / 14) = 3/7
Answer:
- 5 = 76
Step-by-step explanation:
= 81
x = 9
