Answer:
158.76 cm²
Step-by-step explanation:
Quadrilateral ABCD is composed of 2 right triangles
Construct the line BD, then
Δ ABD and Δ BCD are the 2 right triangles.
The area (A) of a triangle is calculated using
A =
bh ( b is the base and h the perpendicular height )
Δ ABD with b = 18 and h = 7.5
A =
× 18 × 7.5 = 9 × 7.5 = 67.5 cm²
Δ BCD with b = 15.6 and h = 11.7
A =
× 15.6 × 11.7 = 7.8 × 11.7 = 91.26 cm²
Thus
area of ABCD = 67.5 + 91.26 = 158.76 cm²

The empirical rule says that approximately 99.7% of any normal distributions falls within three standard deviations of the mean, which leaves 0.3% outside that range, and due to the distribution's symmetry, 0.15% to either side. This means


So

or about 99.9%.
Answer:
Step-by-step explanation:
r(x)= (x-3)(x+5)
= x²+5x-3x-15
=x²+2x-15
Answer:
CFD = 180
EFD= 152
180-152= 28
CFE= 28
Step-by-step explanation: