An object is thrown upward from the top of an 80ft tower.
the height h of the object after t seconds is represented by the quadratic equation h= -16t^2 + 64t + 80.

after how many seconds will the object hit the ground?

a. 29 seconds
b. 6.4 seconds
c. 5.0 seconds
d. 8.0 seconds

Radii ok and nl are perpendicular to om because of the radius-tangent theorem. by definition of perpendicular, angles kom and lnm are right angles. this means that triangles kom and lnm are right triangles. angle lmn is common to both right triangles, so by the triangles kom and lnm are similar.

Find the area of the triangle formed by the origin and the points of intersection of parabolas y=−3x^2+20 and y=x^2−16.

Ateacher brought a pack of 17 batteries . each calculator uses 3 batteries . how many calculator can the teacher fill with batteries