In a right triangle abc, angle c is a right angle and cos b =255/257.

what is the measure or angle a?

a)7.2 degrees

b)83.2 degrees

c)82.8 degrees

d)90.0 degrees

C

Step-by-step explanation:

Given

cosB = = =

Then the hypotenuse AB = 257 and BC = 255

sinA = = =

A = () = 82.8° → C

if the eqn of the parabola is f(x) = (x-4)(x+2), we need to mult. this out to find the coordinates of the vertex.

then f(x) = x^2 + 2x - 4x - 8, and f(x) = x^2 - 2x - 8.

one way in which you can find the vertex is to calculate x = -b / (2a).   here, that comes to

        )

x = = 1.   f(1) = 1^2 - 2(1) - 8 = - 9.   vertex is at (1, -9).

        2(1) 

find another point on the curve:   let x=0, for which y=-8.   then (0, -8) is on the curve.   plot the vertex and this point and draw a smooth parabola thru both.

hope this

1,918

step-by-step explanation: