Question

How to solve Y=2x-1 2x+y=3 in solving systems using substitution

Answer 1

x = 1, y = 1

Explanation:

This Question involves the concept of Solving Simulteanous Equations.

Simulteanous Equations

Simulteanous Equations are 2 sets of equation with 2 unknownes to solve. Methods used are Substitution and Elimination methods, use either to solve unless question specify a method.

Example:

2x + 4y = 67

3x + 9y = 90

Application

We are given the 2 equations:

y = 2x - 1 (Equation 1)

2x + y = 3 (Equation 2)

We are asked to use the Substitution Method.

We first substitute Equation 1 to Equation 2 to find the value of x.

2x + (2x - 1) = 3

2x + 2x - 1 = 3

4x - 1 = 3

4x = 3 + 1

4x = 4

x = 4 ÷ 4 = 1

Now we can substitute x into Equation 1 to find the value of y.

y = 2(1) - 1

y = 2 - 1 = 1