Question

HELP PLS helppppppppppppppppppppppppp

Answer 1

The number of text messages is 85 ⇒ B

Explanation:

To solve this question

• Assume that the number of the text message is x and the total cost is y

• Make a linear equation represented each plan, then equate their total cost (y) to find the number of the text message (x)

The form of the linear equation is y = m x + b, where

• m is the rate

• b is the initial value

Plan A:

∵ The fee per message is $0.10

∴ m = 0.10

∵ The monthly fee is $35

∴ b = 35

∴ The total cost y = 0.10 x + 35

Plan B:

∵ The fee per message is $0.30

∴ m = 0.30

∵ The monthly fee is $18

∴ b = 18

∴ The total cost y = 0.30 x + 18

∵ Both plans cost is the same for one month

→ Equate the right sides of the two equations

∴ 0.30 x + 18 = 0.10 x + 35

→ Subtract 0.10 x from both sides

∴ 0.30 x - 0.10 x + 18 = 0.10 x - 0.10 x + 35

∴ 0.20 x + 18 = 35

→ Subtract 18 from both sides

∴ 0.20 x + 18 - 18 = 35 - 18

∴ 0.20 x = 17

→ Divide both sides by 0.20

∴
`(0.20x)/(0.20)=(17)/(0.20)`

∴ x = 85

∴ The number of text messages is 85