We turn -5,12 into polar coordinates. It's a Pythagorean Triple so
r = 13 Ф=arctan(-12/5) + 180° ( in the second quadrant )
so -5 = 13 cos Ф, 12 = 13 sin Ф
12 sin x - 5 cos x = 6.5
13 sinФ sin x + 13 cos Ф cos x = 6.5
13 cos(x - Ф) = 6.5
cos(x - Ф) = 1/2
cos(x - Ф) = cos 60°
x - Ф = ± 60° + 360° k integer k
x = Ф ± 60° + 360° k
x = 180° + arctan(-12/5) ± 60° + 360° k
That's the exact answer;
x ≈ 180° - 67.38° ± 60° + 360° k
x ≈ 122.62° ± 60° + 360° k
x ≈ { 62.62°, 182.62°} + 360° k, integer k
5:9 is just 5/9
Hope this helps!
Answer:
A
Step-by-step explanation:
<u>Slope- intercept </u><u>form</u>
y= mx +c, where m is the slope and c is the y-intercept.
The given equation is in the slope-intercept form and hence we can easily identify its slope by looking at the coefficient of x.
y= 2x +7
slope= 2
Parallel lines have the same slope, thus the slope of the parallel line is also 2.
Substitute m= 2 into the general equation:
y= 2x +c
Substitute a pair of coordinates into the equation to find the value of c:
When x= 3, y= 11,
11= 2(3) +c
11= 6 +c
c= 11 -6
c= 5
Therefore the equation of the line is y= 2x +5.
If each inch is 40 miles then 7(40) = 280 and add the 1/4 which is 10 so the answer is 290
