Element X decays radioactively with a half life of 6 minutes. If there are 900 grams of Element X, how long, to the nearest tenth of a minute, would it take the element to
decay to 121 grams?
y = a(.5)

t = 17.4 minutes

Step-by-step explanation:

p = a(1/2)^(t/h)

121 = 900(1/2)^(t/6)

Divide both sides by 900

0.1344444444 = (1/2)^(t/6)

Take the log of both sides

log0.1344444444 = (t/6)log(1/2)

Divide both sides by log(1/2)

log0.1344444444 / log(1/2) = t/6

multiply both sides by 6

6 * log0.1344444444 / log(1/2) = t

use calculator

17.369507726516199 = t

rounded

t = 17.4 minutes

solution:

we have to construct

∠m nt ≅ ∠p qr

the steps to draw this construction are

step 1: use a compass to draw an arc from point q which intersects the side pq at point a and the side qr at point b.

step 2: draw a segment nt and use the same width of the compass to draw an arc from point n which intersects the segment nt at a point x.

step 3:

step 4: join points n and y using a straightedge.

step 3:

option (d).maintaining the same width of the compass as ab, draw an arc from point x such that it intersects the arc drawn from n in a point y.

to draw   congruent angles , 1. width of compasses while drawing two angles should be same i.e from point at which angle has to be drawn, 2.the distance between the two points where the compass intersects the two sides should be same while drawing any two congruent angles.

c

step-by-step explanation: