The triangle formed from the height of the cone and the radius of its base is a special 3,4,5 triangle. The slant height is 5cm.
Recall that the area of a circle = pi*r^2
Substitute 3 in for r
Area = pi * (3)^2 = 9pi
SA = pi*r*l + B
Substitute our values into the equation
SA = pi * 3 * 5 + 9pi
SA = 15pi + 9pi
SA = 24pi cm^2
The equation is option number c because someth = smth
A method that always works is to find the slope of the given line, then find the negative reciprocal of that. Your result will be the slope of the perpendicular line. Using this slope and the given point, fill in the parameters of the point-slope form of the equation of a line.
For m = slope of given line and (h, k) = given point, the perpendicular line will be
y = (-1/m)(x -h) +k
Often, this equation can be simplified to another appropriate form, such as slope-intercept form (y = mx+b) or standard form (ax+by=c).
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The slope of a given line can be found by solving its equation for y. The slope is the coefficient of x in that solution. If the given line is characterized by two points, (x1, y1) and (x2, y2), then its slope is m = (y2-y1)/(x2-x1).
In the unusual case where the given line is vertical (x=<some constant>), the slope of the perpendicular line is zero, and the line you want becomes y=k.
