The depth of the water at the end of a pier changes periodically along with the movement of tides. on a particular day, low tides occur at 12: 00 am and 12: 30 pm, with a depth of 2.5 m, while high tides occur at 6: 15 am and 6: 45 pm, with a depth of 5.5 m. let t = 0 be 12: 00 am. write a cosine model, d = acos(bt) + k, for the depth as a function of time. this amplitude is meters. a =

the correct option is 2.

step-by-step explanation:

according to the given information triangle abc is a right angle triangle with right angle at a. segment ab is 5 and segment ac is 7. point d is on segment bc and angles adb and adc are right angles.

it is given that triangles abd, cad, and cba are similar.

two triangles are similar if their corresponding sides are proportional.

in triangle cba, using pythagoras theorem

                      )

triangle abd and cba are similar,

                            (2)

triangle cad and cba are similar,

                      )

using (1), (2) and (3), we get

hence proved.

therefore option 2 is correct.

y = 3x+4

step-by-step explanation:

to find the slope

slope = (y2-y1)/ (x2-x1)

    = (-8-4)/ (-4-0)

    = -12/-4

  = 3

using the slope intercept form of a line

y= mx+b

we know the slope is 3

we know the y intercept is 4 ( the point where it crosses the y axis or x=0)

y = 3x+4