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A plant is 5cm tall and growing at a rate of 3cm a month. How many months would it take for the plant to reach 23cm?

User JKennedy
by
3.4k points

2 Answers

5 votes

Answer:

plant b height will exceed the height of plant a after 16 days.

Explanation:

Plant a: 5 cm tall and rate of change = 3 cm per month

Plant b: 4 cm tall and rate of change = 5 cm per month.

Now we have to form the linear equations.

Plant a:

y = 3x + 5, where y is the total height and "x" be the number of months.

Plant b:

y = 5x + 4 , where y is the total height and "x" be the number of months.

Now we have to when the height of the plant a and plant b are the same.

To do that, we have to equivate both the equations and find x.

3x + 5 = 5x + 4

Isolate the variables terms and constants.

5x - 3x = 5 - 4

2x = 1

Dividing both sides by 2, we get

x = 1 ÷ 2

x = 0.5 months.

So after 15 days, the height of the plant a and plant b are the same.

Therefore, plant b height will exceed the height of plant a after 16 days.

User Ramon Balthazar
by
3.1k points
3 votes

Answer:

6 months

Explanation:

5cm +3x = 23 (goal)

-5 -5

3x=18

x=6 months

User Aruna Karunarathna
by
3.4k points