a car travels along a straight road heading east for one hour, then traveling for 30 minutes on another road that leads northeas
t. if the car has maintained a constant spead of 40 miles per hour, how far is it from the starting position/
1 answer:
Answer:
55.96 miles
Step-by-step explanation:
Distance = Speed X time
Car first moved east for 1 hr , distance = 40 x 1 = 40 miles
Car then moved north-east for 30 min, distance = 40 x 0.5 = 20 miles
From trigonometry,
sin 45 = ; y = 20 sin 45 ; y= 14.14 miles
cos 45 = ; x = 20 cos 45 ; x = 14.14 miles
using Pythagoras theorem;
=
+
= +
= 3131.08
=
z = 55.96 miles
You might be interested in
Answer:
<h2>4/3 Joules </h2>Step-by-step explanation:
Work is said to be done when force applied to an object causes the object to move through a distance.
Work done = Force * perpendicular distance.
Given Force F = xy i + (y-x) j and a straight line (-1, -2) to (1, 2)
First we need to get the equation of the straight line given.
Given the slope intercept form y = mx+c
m is the slope
c is the intercept
m = y₂-y₁/x₂-x₁
m = 2-(-2)/1-(-1)
m = 4/2
m = 2
To get the slope we will substtutte any f the point and the slope into the formula y = mx+c
Using the point (1,2)
2 = 2+c
c = 0
y = 2x
Substituting y = 2x into the value of the force F = xy i + (y-x) j we will have;
F = x(2x) i + (2x - x) j
Using the coordinate (1, 2) as the value of s
Answer:
-10
Step-by-step explanation:
You are asked to tell the y-value of the solution. You can find the whole solution and then report the y-value, or you can just find the y part of the solution. We choose the latter.
This is basically done by eliminating the x-variable. It can be done using the "elimination" method of solving these equations. And it can also be done using the "substitution" method of solving these equations. We choose the latter.
Add 14 to the second equation to solve for x:
... x = y + 14
Substitute this into the first equation.
... 3(y +14) -y = 22
... 2y +42 = 22 . . . . . . simplify
... y +21 = 11 . . . . . . . . divide by 2
... y = -10 . . . . . . . . . . subtract 21
_____
<em>Comment on additional solution methods</em>
A graphing calculator can show you the solution, as in the attachment. Of the solution (x, y) = (4, -10), we are only interested in y = -10.
Cramer's rule can find just one variable value, too. For that, it is convenient to write the system as ...
- 3x -y = 22
- x - y = 14 . . . . . add 14-y to the equation given
Then the solution for y is ...
... y = (22·1 -14·3)/(-1·1 -(-1)·3) = -20/2 = -10
