Awooden plank is leaning against a wall. the bottom of the plank is 3 feet from the wall. answer each of the following questions, and show all your work.(a) find ac, the approximate length of the plank. round to the nearest tenth of a foot.(b) find bc, the height off the ground where board touches as wall. round to the nearest foot.

AB = ==> distance between the bottom of the plank; and the wall ===> 3 ft.

C > 49 degrees

For letter a, to solve for AC:

AC ==> HYPOTENUSE. The angle C is the OPPOSITE side of AB.

use sine :

sin A ===> opposite/hypotenuse

Solve:

sin 49 > 3/AC

AC > 3 / sin 49

AC > 3.96 ft.

For letter b, to solve for BC:

We are now given with the base (3 ft.); and; the hypotenuse (3.96 ft.) so we can use the Pythagorean theorem:

a^2 + b^2 = c^2

Let:

a ===> AB

b ===> BC

c ===> AC

(AB)^2 + (BC)^2 ===> (AC)^2

3^2 + (BC)^2 ===> (3.96)^2

(BC)^2 ===> (3.96)^2 - 3^2

(BC)^2 ===> 6.6816

sqrt (BC)^2 ===> sqrt 6.6816

BC ===> 2.58 ft.

Hope that helps : )

80° is the measure of gh

step-by-step explanation:

circle f is congruent to circle j

we have two circle with center f and j.

both circles are congruent. the radius of the circle would be equal.

see the attachment for the circle.

we are given ∠efd ≅ ∠gjh

therefore, arc (ed) = arc (gh)     (∴ circle f is congruent to circle j)

but ∠dfe=80°=arc (ed)

therefore, arc (gh) = 80°

thus, 80° is the measure of gh