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Solve Linear equations with two unknowns 21x+7y=42;-5+5y=10

User Sita
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Final answer:

To solve the system of linear equations, the second equation is simplified to find y=3, which is substituted into the first equation to find x=1, resulting in a solution of x=1 and y=3.

Step-by-step explanation:

To solve the given linear equations with two unknowns, 21x+7y=42 and -5+5y=10, we can follow a step-by-step method. Let's start by simplifying and rewriting the equations if necessary, then use either substitution or elimination methods to find the values of x and y.

First, let's simplify the second equation:

  • -5 + 5y = 10
  • Add 5 to both sides to isolate the term with y: 5y = 15
  • Divide both sides by 5 to solve for y: y = 3

Having found that y = 3, we can substitute it into the first equation to find x:

  • 21x + 7(3) = 42
  • 21x + 21 = 42
  • Subtract 21 from both sides: 21x = 21
  • Divide both sides by 21: x = 1

Now we have the solution to the system of equations, which is x = 1 and y = 3.

It is important to note that linear equations are generally in the form y = a + bx, where 'a' is the y-intercept, 'b' is the slope, 'x' is the independent variable, and 'y' is the dependent variable. This form applies to a multitude of real-world situations, such as relating the number of flu cases to the year or determining the total cost based on the number of years enrolled in an institution.

User Magnus Engdal
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