Respuesta :

Answer:

[tex]c=18.90-2.1r[/tex]

Step-by-step explanation:

The complete question is

A chef bought $17.01 worth of ribs and chicken. Ribs cost 1.89 per pound and chicken costs 0.90 per  pound. The equation 0.90 +1.89r = 17.01 represents the relationship between the quantities in this  situation.

Show that each of the following equations is equivalent to 0.9c + 1.89r = 17.01.

Then, explain when it might be helpful to write the equation in these forms.

a. c=18.9-2.1r. b. r= -10÷2c+9​

we have that

The linear equation in standard form is

[tex]0.90c+1.89r=17.01[/tex]

where

c is the pounds of chicken

r is the pounds of ribs

step 1

Solve the equation for c

That means ----> isolate the variable c

Subtract 1.89r both sides

[tex]0.90c=17.01-1.89r[/tex]

Divide by 0.90 both sides

[tex]c=(17.01-1.89r)/0.90[/tex]

Simplify

[tex]c=18.90-2.1r[/tex]

step 2

Solve the equation for r

That means ----> isolate the variable r

Subtract 0.90c both sides

[tex]1.89r=17.01-0.90c[/tex]

Divide by 1.89 both sides

[tex]r=(17.01-0.90c)/1.89[/tex]

Simplify

[tex]r=9-0.48c[/tex]

therefore

The equation [tex]c=18.90-2.1r[/tex] is equivalent

The equation is helpful, because if I want to know the number of pounds of chicken, I just need to substitute the number of pounds of ribs in the equation to get the result.