# Svetlana's hair is 4 centimeters long. Her hair grows 1.5 centimeters per month. Svetlana wants her hair to grow so that it is at least 7 centimeters long. How many months, #m#, will it take Svetlana's hair to grow so it is at least 7 centimeters long?

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Write an inequality.

Write an inequality.

##### 2 Answers

2 months.

#### Explanation:

first subtract Svetlana present hair length from the desired hair length in order to find out how much growth is required.

Next divide the 3 cm needed to reach the desired length by the rate of growth to find the number of months.

Answer:

#### Explanation:

We are given the current length of hair as

#gm+b>=r#

where#g# is the slope or growth rate in centimeters,#m# as our variable for number of months,#b# is the starting length in centimeters, and#r# is the required length in centimeters.

Plugging in our values, we have:

To find the number of months,

Therefore, it will take at least 2 months for her hair to be at least 7 centimeters