Answer:
5n + 10d represented the money spend by the Amy in playing board games of cost $5 and $10 .
Step-by-step explanation:
As given
Amy and Mary are playing a board game that uses game money if $5 and $10.
At the end of the game, Amy has n bills worth $5 each and d bills worth $10 each .
Total amount of n bills = 5n
Total amount of d bills = 10d
Thus
Total money spend by the Amy in playing board games = Total amount of n bills + Total amount of d bills
= 5n + 10d
Therefore 5n + 10d represented the money spend by the Amy in playing board games of cost $5 and $10 .
Answer:
The correct answer for the second one is,

Answer:
13 and 16
Step-by-step explanation:
let the 2 parts be x and y, then
x + y = 29 → (1) and
x² + y² = 425 → (2)
From (1) → x = 29 - y → (3)
substitute x = 29 - y into (2)
(29 - y)² + y² = 425 ( expand factor )
841 - 58y + y² + y² = 425 ( rearrange into standard form )
2y² - 58y + 416 = 0 ← in standard quadratic form
divide all terms by 2
y² - 29y + 208 = 0
Consider the factors of 208 which sum to - 29
These are - 13 and - 16, hence
(y - 13)(y - 16) = 0
equate each factor to zero and solve for y
y - 13 = 0 ⇒ y = 13
y - 16 = 0 ⇒ y = 16
substitute these values into (3)
x = 29 - 13 = 16 and x = 29 - 16 = 13
The 2 parts are 13 and 16
replace the value of x int eh equation
so 23x-1 becomes
23(1.1478)-1
23*1.1478 = 26.3994-1 = 25.3994
The first expression is equivalent to B
The second expression is equivalent to A
The third expression is equivalent to C
You are basically adding like terms. For example for the first expression, it is 7x^2 + 2x^2, which equals 9x^2. Remember since you're adding, do not add the exponents.