Question #1If a 30-foot silo casts a 20-foot shadow, what is the approximate measure from the tip of the shadow to the top of the silo?a, 1,300 feetb, 36 feetc, 650 feetd, 13 feetQuestion #2If the measure of a central angle is 76°, then what is the measure of the arc it creates?a, 152°b, 76°c, 38°d, 19°Question #3Which regular polygon would have each of its interior angles measure 140°?a, nonagonb, heptagonc, octagond, decagon
What school do you go to? Western christian academy?
1) The silo and the shadow are at right angle to each other, so this makes a right triangle where the hypotenuse is the measure from the tip of the shadow to the top of the silo. Use the Pythagorean Theorem and round your answer. 2) If θ is the angle in RADIANS, then the arc is r θ. But since they don't give the radius, I'm guessing they mean the arc as measured by it's central angle. So it's 76 degrees. 3) Look in your book for the formula giving the interior angle of a polygon in terms of n. Set it equal to 140 and solve for n.
1) 30^2+20^2=c^2 or c^2=1300 so c=sqrt 1300 or c=about 36 ft. so choice B 2) 76 deg. so choice B 3) (n-2)*180=140n so 180n-360=140n or 40n=360 or n=9 so 9 sides Choice A
