Quick Homework Help

# ok i figured out all of my 13 probs except these 3 please help me with them ⚑ Flag

by dave226 at June 13, 2011

1. Give sec x= 2.375 and 0degrees<x<360 find all the values of x to the nearest degree 2. Find the length of the major axis of the following ellipse ((x +7)^2) /9 + ((y -2)^2) /16 3. Given the following Hyperbola find the equation of the asymptotes 9x^2 â€“ y^2 - 90x â€“ 4y +185 = 0Top of Form

Dave -sec x = 2.375 can be re-written as:1/cos x = 2.375, now simply invert both sides:cos x = 1/2.375 = 0.42105cos x is positive in Quadrant I and IV.arccos(0.42105) = So, this answer makes sense, since it is in Quadrant I. The other answer is in Quadrant IV. It is a reflection of the first answer over the x-axis. It equals -But, -equals 360 -65 = So, the answers are 65 and 295 degrees.Hope that helps

Steve204 June 13, 2011

2. For an ellipse, the major axis is always the bigger denominator.  Here, 16 is bigger than 9, agree.  So, the major axis is parallel to the y-axis.Using the standard form for an ellipse:16 = a^2 , where a is equal to half the length of the major axis.  Since a = 4, then double that equals 8. So, the length of the major axis is 8.

Steve204 June 13, 2011

For #3, you have to complete the square twice ... once for the x variable and once for the y variable.After you complete the squares and you have the hyperbola in standard form and set equal to 1, the formula for the asymptotes are:(y - k) = ± m(x - h)where, (h,k) = center of hyperbolam = slope of the line. The slope is simply the square root of the denominator under the y-term divided by the square root of the denominator under the x-term.

Steve204 June 13, 2011