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The Skateboard club has 2 different colors of skateboards blue and red. Can you find the number of skateboards of each color, if the total number of skateboards is 15, and their product is 44?

1 Answer

6 votes

Answer:

The number of skateboards of each color is 11 and 4

Explanation:

Let x represent blue skateboards and

y represent red skateboards.

From the question, the total number of skateboards is 15, that is,

x + y = 15 ...... (1)

and their product is 44, that is,

xy = 44 ...... (2)

From equation (1),

x + y = 15

We can write that

x = 15 - y ...... (3)

Substitute this into equation (2)

xy = 44

(15-y)y = 44

15y -y² = 44

Then,

y² - 15y + 44 = 0

Solve quadratically

y² -4y -11y + 44 = 0

y(y-4) -11(y-4) = 0

(y-11)(y-4) = 0

y-11 = 0 OR y-4 = 0

y = 11 OR y = 4

Put the values of y into equation (3) for x

x = 15 - y

When y = 11

x = 15 - 11

x = 4

and when y = 4

x = 15 -4

x = 11

(4,11) and (11,4)

It is either 4 blue and 11 red skateboards OR 11 blue and 4 red skateboards.

Hence, the number of skateboards of each color is 11 and 4.

User Brandon Gano
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