Use the substitution method
w(x)=9x+8
w(5)=9(5)+8
Do the parenthesis first then add because of using PEMDAS
P= Parentheses
E= Exponents
M= Multiplication
D= Division
A= Addition
S= Subtraction
45+8
=53
Answer: w(5)=53
Length (L): w + 3.5
width (w): w
Perimeter (P) = 2L + 2w
31 = 2(w + 3.5) + 2(w)
31 = 2w + 7 + 2w
31 = 4w + 7
24 = 4w
6 = w
Length (L): w + 3.5 = (6) + 3.5 = 9.5
Answer: width = 6 inches, length = 9.5 inches
Since BC is the hypotenuse...
α = 12
c = 13
Hence..
13² = 12² + ß²
ß = √(13² - 12²)
= √(169 - 144)
= √25
= 5
Hence, AB = 5
I hope this helps!
(a)

(b)we have 4 terms in this expression.
(c)+12 is the leading coefficient in

(d) constant is -45