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I don’t get it, help pls

I don’t get it, help pls-example-1
User Dsturbid
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1 Answer

4 votes

2) The solutions for x and y in terms of each other are x = 77 - 2y and y = 38.5 - 0.5x respectively.

3) In the equation, c = 18.9 - 2.1r, it is equivalent to 0.9c + 1.89r = 17.01. Similarly, in the equation, r = -
(10)/(21)c + 9, it is equivalent to 0.9c + 1.89r = 17.01.

2) Given Equation: 2x + 4y - 31 = 123

Variables = x and y

To solve for x, we rearrange the equation thus:

2x = 123 + 31 - 4y

x = (154 - 4y) ÷ 2

x = 77 - 2y

To solve the equation for y:

4y = 123 + 31 - 2x

y = (154 - 2x) /÷ 4

y = 38.5 - 0.5x

Thus, the solutions for x and y in terms of each other are x = 77 - 2y and y = 38.5 - 0.5x respectively.

3) The total cost of purchasing ribs and chicken = $17.01

The cost per pound of ribs = $1.89

The cost per pound of chicken = $0.90

Given equation:

0.9c + 1.89r = 17.01

a) Make c the subject of the equation by isolating it in the original equation:

0.9c = 17.01 - 1.89r

Divide all terms by 0.9:

c = 17.01 ÷ 0.9 - 1.89r ÷ 0.9

c = 18.9 - 2.1r

This equation is equivalent to 0.9c + 1.89r = 17.01.

b) Make r the subject of the equation by isolating it in the original equation:

0.9c = 17.01 - 1.89r

Divide all terms by 1.89:

r = 17.01/1.89 - 0.9c/1.89

r = 9 - 1/2.1c

r = 9 - 10/21c

r = -
(10)/(21)c + 9

This equation is also equivalent to 0.9c + 1.89r = 17.01.

Thus, we write the equations in these forms when solving for one variable in terms of the other, especially if the chef wants to know how many ribs he can buy for a certain amount of chicken, and vice versa.

User Pedro Justo
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