Answer:
Part 1)

Part 2)
Part 3)

Part 4)

Explanation:
Part 1)
Let
x-----> the number
The expression" Five times a number decreased by nine is equal to twice the number increased by
", is equal to the algebraic expression

Part 2) we have that



Let
x------> the number of nickels
y-------> the number of dimes
z-------> the number of quarters

Multiply by
both sides
------> equation A
-----> isolate the variable y
------> equation B
------> equation C
substitute equation B and equation C in equation A
Part 3) we know that
Let
x------> the number
The equation that represent the expression is equal to

Part 4) we have

Multiply by
both sides




