Answer:
see explanation
Step-by-step explanation:
The sum of the 3 angles in a triangle = 180°, thus
∠1 = 180° - (72 + 57)° = 180° - 129° = 51°
The right angle at the left vertex is composed of 72° and ∠2, thus
∠2 = 90° - 72° = 18°
57° and ∠3 form a straight angle and are supplementary, thus
∠3 = 180° - 57° = 123°
∠4 = 180° - (∠2 + ∠3 ) ← sum of angles in a triangle
∠4 = 180° - (18 + 123)° = 180° - 141° = 39°
Surface Area of the figure is 1208 square centimeters
a=20
b=13
c=12
d=5
e=8
Top face:
A1=a×e=20×8
ae=160
Bottom face:
A2(a+2d)×e=(20+2×5)×8=(20+10)×8=30×8
(a+2d)e=240
Front face:
Rectangle
a×c=20×12=240
Triangle:
12c×d=12×12×5=6×5=30
A3Rectangle +2 triangles
240+2×30=240+60=300
(a+d)c=300
Slant face:
A4=b×e=13×8=104
be=104
Total surface area
A=A1+A2+2(A3+A4)
A1=160
A2=240
A3=300
A4=104
Thus,
A=160+240+2(300+104)
A=400+2(404)
A=400+808=1208
Surface Area of the figure is 1208 square centimeters
Answer:
A = 450 cm²
Step-by-step explanation:
Since the right triangle is isosceles then the 2 logs are congruent , both 30 cm and at right angles to each other.
The area (A ) of the triangle is calculated as
A =
bh ( b is the base and h the perpendicular height )
Here b = h = 30 , then
A =
× 30 × 30 =
× 900 = 450 cm²
950 - 50 = 900
900 / 2 = 450
The bench cost $450 and the garden table cost $500
Your answer is $450
Hope this helps!