Answer:
The light intensity at a depth of 24 feet is 3.0143 lumens.
The light intensity will be 7 lumenus at the depth of 9.3732 feet approximately.
Step-by-step explanation:
Consider the provided formula.
Where I is the intensity of light and x is the depth.
Part (A) Find the light intensity at a depth of 24 feet.
Substitute x=24 in above formula.
Hence, the light intensity at a depth of 24 feet is 3.0143 lumens.
Part (B) At what depth is the light intensity 7 lumens
Substitute I=7 in above formula.
Hence, the light intensity will be 7 lumenus at the depth of 9.3732 feet approximately.
Answer:
a. y + 9 + x + y + x + 4 + x + 5 = 2x + 2y + 18
b. 30.4cm
c. Area of big rectangle = 9y cm², Area of small rectangle = 4x cm²
d. a = 9y + 4x
e. a = 38.8
Step-by-step explanation:
a. Perimeter = y + 9 + x + y + x + 4 + x + 5
= x + x + y + y + 9 + 4 + 5
= 2x + 2y + 18
b. 2x + 2y + 18 = 2(3.4) + 2(2.8) + 18
= 6.8 + 5.6 + 18
= 30.4cm
c. Formula for area of rectangle: length × breadth
Area of big rectangle = 9 × y
= 9y cm²
Area of small rectangle = 4 × x
= 4x cm²
d. a cm² = (9y + 4x)cm²
e. a = 9y + 4x
= 9(2.8) + 4(3.4)
= 25.2 + 13.6
= 38.8
Answer:
41 + 11i
Step-by-step explanation:
Note that i² = - 1
Given
(3 - 5i)(2 + 7i) ← expand using FOIL
= 6 + 21i - 10i - 35i² ← collect like terms
= 6 + 11i + 35
= 41 + 11i
First get all the terms on the same side:
Now solve using the quadratic formula which is:
Plug in the values:
So the answer is:
complex roots occur in conjugate pairs
given 2 - 3√5 is a root then 2 + 3√5 is also a root
one of the other roots is 2 + 3√5
there are 2 roots of - 4
one of the other roots could be another - 4
