Question

Using substitution and elimination method solve this simultaneous equation
Y=x+1
X+Y=3

Answer 1

x = 1 and

Y = 2

Explanation:

1. Y = x + 1

2. X + Y = 3

Substitute equation 1 into equation 2

X + Y = 3

X + X + 1 = 3

2x + 1 = 3

Subtract 1 from both sides to eliminate 1 on the left side

2x + 1 - 1 = 3 - 1

2x = 2

Divide both sides by 2 to isolate x

2x/2 = 2/2

x = 1

Substitute 1 for x in either equation to get Y

Using equation one, we have

Y = x + 1

= 1 + 1

= 2

x = 1

Y = 2

Check

X + Y = 3

1 + 2 = 3

3 = 3