Explain this and what method? Is it linear combos or some sort of GCF finding

just subtracting the expression for revenue from the expression for cost

Step-by-step explanation:

  2x^3 + 30x - 130

-  2x^3 - 3x - 520

(subtracting means adding the opposite)

2x^3 - 2x^3 = 0

30x - (-3x) = 33x

-130 - (-520) = 390

146%

step-by-step explanation:

all three statements are true

step-by-step explanation:

a shipping fee of 5% is charged online with every item purchased online

first let's just take each option and calculate them based on this, to see if the answers matched

keith buys a 40 dollar book

40 x 0.05 = 2

therefore there will be a two dollar fee on keith's book

40 + 2 =42

the first statement is true

a chair costs $80

80 x 0.05 = 4

80 + 4 = 84

the second statement is true

george buys a 20 dollar calculator

20 x 0.05 = 1

20 + 1 = 21

the third statements are true

all three statements are true