Rafael counted a total of 40 white cars and yellow cars there were 9 times as many white cars as yellow car how many white cars did Rafael count

According to the given information he counts 9 times as many white cars as yellow car. It means the number of white cars counted by rafael is 9 times of the yellow cars.

[tex]x=9y[/tex] ......(2)

Put [tex]x=9y[/tex] in equation (1).

[tex]9y+y=40\\10y=40\\y=4[/tex]

Put [tex]y=4[/tex] in equation (1).

[tex]x+4=40\\x=36[/tex]

Since x is the number of white cars, therefore number of white cars counted by Rafael is 36.

ardni313 ardni313 · Answer 2 · 2019-08-02T22:06:42-04:00

White cars did Rafael count = 36 cars

Further explanation

A two-variable linear equation system is an equation that involves 2 variables (the value that can change) and the equation has the highest rank of 1

In this equation system there are coefficients and variables whose solutions can use:

1. substitution

2. elimination

3. graph

4. mix

Steps for completion with the substitution method:

1. change one of the equations to the form y = ax + b or x = ay + b

2. substitution the value of x / y to another equation

3. solve the equation

4. substitution results from point 3 in one equation

In the statement of the question mentioned Rafael counted the number of white cars and yellow cars = 40 pieces so that the equation:

w + y = 40 ---- equation 1

w = white car

y = yellow car

Then Rafael concluded that white cars were nine times the yellow cars, so the equation was

w = 9y ... equation 2

So that the solution

1. equation 2, we enter into equation 1

9y + y = 40

10 y = 40

y = 4

2. We enter the value of y into one of the equations

w = 9y

w = 9.4

w = 36

So we get 36 white cars

Learn more

the substitution method

https://brainly.com/question/11705106

https://brainly.com/question/7162056

The work of a student to solve a set of equations

https://brainly.com/question/10589573

Keywords: the substitution method, elimination, graph, a two-variable linear equation system