White cars did Rafael count = 36 cars
<h3><em>Further explanation</em></h3>
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:
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
- 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
<h3><em>Learn more</em></h3>
the substitution method
brainly.com/question/11705106
brainly.com/question/7162056
The work of a student to solve a set of equations
brainly.com/question/10589573
Keywords: the substitution method, elimination, graph, a two-variable linear equation system