x+142 =3x+64
subtract x from each side
142 = 2x+64
subtract 64 from each side
142-64 = 2x
78=2x
divide by 2
78/2 = x
x=39
The number is 39
We'll use standard labeling of right triangle ABC, C=90 degrees, legs a, b, hypotenuse c.
11.
Right triangle, cliff peak A, boat B, angle opposite cliff is B=28.9 deg. adjacent leg a=65.7 m, cliff height is leg b.
tan B = b/a
b = a tan B = 65.7 tan 28.9° = 36.3 m
12.
Similar story, boat at B, opposite b=3.5 m, rope c=12 m
sin B = b/c
B = arcsin b/c = arcsin (3.5/12) = 17.0°
13.
c=124 m, A=58°
sin A = a/c
a = c sin A = 124 sin 58 = 105.2 m
14.
That's a hypotenuse c=4-1.2 = 2.8 m to a height b=1.8m so
cos A = b/c
A = arccos b/c = arccos (1.8/2.8) = 50.0°
15.
Not a right triangle, an isosceles triangle. Half of it is a right triangle with hypotenuse one arm, c=9.8 cm and angle opposite half the base of B=62/2=31°. We're after d=2b:
sin B = b/c
b = c sin B
d = 2b = 2 c sin B = 2(9.8) sin 31 = 10.1 cm
Almost equilateral
Sorry I don’t know the answer and the question to
Answer:

Step-by-step explanation:
step 1
Find the volume of the cylinder
The volume of the cylinder is equal to

we have
---> the radius is half the diameter

substitute

step 2
Find the volume of the cone
The volume of the cone is equal to

we have
we have
---> the radius is the same that the radius of the cylinder

substitute

step 3
Find the volume of the plastic object
we know that
The volume of the plastic object is equal to the volume of the cylinder minus the volume of the cone
so

assume


Answer:
2 Gallons are needed to cover entire wall