Answer:
100°
Step-by-step explanation:
The sum of the 3 angles in a triangle = 180°, thus
∠ACB = 180° - (90 + 50)° = 180° - 140° = 40°
∠ECD = 40° ( vertical angle to ∠ACB )
Since CE ≅ ED then ΔCDE is isosceles and
∠CDE = ∠ECD = 40°
∠E = 180° - (40 + 40)° = 180° - 80° = 100°
Answer:
408 sq. in.
Step-by-step explanation:
The total surface area of the pyramid is the sum of all 4 faces (each of them a triangle) and square base.
Triangle area is where b is base and h is height.
base of triangle is 12 and height is 11
So area of each triangle is
There are 4 of them, so total is 66 * 4 = 264
Now, square has an area of where s is the side length.
It is given s = 12, so the area of the square base is:
Total Surface Area of the Pyramid is 264 + 144 = 408 sq. in.
Answer:
?
Step-by-step explanation:
One side is -4.
It can also be x + 4.
Turn 16 + 8x + x^2 into standard form —> x^2 + 8x + 16
Note: standard form is ax^2 + bx + c
Use the “foil” method to factor.
(x + 4)(x + 4)
x=-4