Juan tiene cubos azules de 55 mm de arista y cubos rojos de 45 mm de arista. los apila en dos columnas, una de cada color ; quiere conseguir que las dos columnas sean igual de altas. ¿cuántos cubos necesita, como mínimo, de cada color?

the question in English

Juan has blue cubes with a 55 mm edge and red cubes with a 45 mm edge. He stacks them in two columns, one of each color; he wants the two columns to be the same height. How many cubes does he need, as a minimum, of each color?

Let

x---------> the number of blue cubes

y--------> the number of red cubes

we know that

Juan wants that  the two columns to be the same height

so

solve for y

I proceed to calculate a table, assuming values of x to calculate the value of y. When the values of x and y are whole numbers, I will have found the solution.    

the table in the attached figure

therefore

the answer is

9 blue cubes

11 red cubes

the equation cos(35) =a/25 can be used to find the length of bc what is the length of bc? round to the nearest tenth

step-by-step explanation:

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18