Answer:
7. 
8. l=11cm and w=7 cm
9. 
10. 
Step-by-step explanation:
Question 7.
The given expression is:

Expand the parenthesis using the distributive property:

Group similar terms:

Simplify

Divide both sides by -10

Question 8:
Let the width of the rectangle be;
The length of the rectangle is 
The perimeter is given as: 
Given that the perimeter P=36, then:
![36=2[(w+4)+w)]](https://tex.z-dn.net/?f=36%3D2%5B%28w%2B4%29%2Bw%29%5D)

Divide both sides by 2:

Subtract 4 from both sides:



The dimensions of the rectangle is: w=7 cm and l=7+4=11cm
Question 9
Let the number be x.
"5 fewer than the number" is written as 
"5 fewer than a number is at least 12" becomes

Question 10:
Let the number be x.
The quotient of a number and 3 is written as:

The quotient of a number and 3 is no more than 15 is written as;

(x - 1)(x - 2)(x + 2)
note that the sum of the coefficients 1 - 1 - 4 + 4 = 0
thus x = 1 is a root and (x - 1 ) is a factor
dividing x³ - x² - 4x + 4 by (x - 1)
x³ - x² - 4x + 4 = (x - 1)(x² - 4 ) (note (x² - 4 ) is a difference of squares )
x³ - x² - 4x + 4 = (x - 1)(x - 2)(x + 2)
(x - 1)(x - 2)(x + 2 ) =0
x - 1 = 0 ⇒ x = 1
x - 2 = 0 ⇒ x = 2
x + 2 = 0 ⇒ x = - 2
solutions are x = 1 or x = ± 2
Step-by-step explanation:
step 1. break up the shape into 2 triangles and one rectangle
step 2. A = area of triangle 1 (t1) + area of triangle 2 (t2) + area of the rectangle (r)
step 3. t1 = (1/2)bh where b is the base and h is the height. definition of the area of a triangle.
step 4. t1 = (1/2)(3)(2) = 3ft^2.
step 5. t2 = (1/2)(3)(3) = 4.5ft^2.
step 6. r = bh where b is the base and h is the height. definition of the area of a rectangle.
step 7. r = bh = (8)(4) = 32ft^2.
step 8. A = t1 + t2 + r = 3 + 4.5 + 32 = 39.5ft^2.
Step-by-step explanation:
(a)
Using the definition given from the problem
![f(A) = \{x^2 \, : \, x \in [0,2]\} = [0,4]\\f(B) = \{x^2 \, : \, x \in [1,4]\} = [1,16]\\f(A) \cap f(B) = [1,4] = f(A \cap B)\\](https://tex.z-dn.net/?f=f%28A%29%20%3D%20%5C%7Bx%5E2%20%20%5C%2C%20%3A%20%5C%2C%20x%20%5Cin%20%5B0%2C2%5D%5C%7D%20%3D%20%5B0%2C4%5D%5C%5Cf%28B%29%20%3D%20%5C%7Bx%5E2%20%20%5C%2C%20%3A%20%5C%2C%20x%20%5Cin%20%5B1%2C4%5D%5C%7D%20%3D%20%5B1%2C16%5D%5C%5Cf%28A%29%20%5Ccap%20f%28B%29%20%3D%20%5B1%2C4%5D%20%20%3D%20f%28A%20%5Ccap%20B%29%5C%5C)
Therefore it is true for intersection. Now for union, we have that
![A \cup B = [0,4]\\f(A\cup B ) = [0,16]\\f(A) = [0,4]\\f(B)= [1,16]\\f(A) \cup f(B) = [0,16]](https://tex.z-dn.net/?f=A%20%5Ccup%20B%20%3D%20%5B0%2C4%5D%5C%5Cf%28A%5Ccup%20B%20%29%20%3D%20%5B0%2C16%5D%5C%5Cf%28A%29%20%3D%20%5B0%2C4%5D%5C%5Cf%28B%29%3D%20%5B1%2C16%5D%5C%5Cf%28A%29%20%5Ccup%20f%28B%29%20%3D%20%5B0%2C16%5D)
Therefore, for this case, it would be true that
.
(b)
1 is not a set.
(c)
To begin with

Therefore

Now, given an element of
it will belong to both sets, therefore it also belongs to
, and you would have that
, therefore
.
(d)
To begin with
, therefore

Answer:
x=3.5 cm
Step-by-step explanation:
90/2 = 45 degrees
Soh Cah Toa
We have opposite and hypotenuse making sin.
Length×Sin(Angle)
5×Sin(45) = 3.53553cm
Rounded the the nearest tenth makes 3.5cm