Question

Solve the systems of equations by subsiturion

y=x+15
y=2x


next question
y=x+12
4x+2y=27​

Answer 1

1) x = 15, y = 30 is the solution of the given system of equation.

2) x = 0.5 , y = 12.5 is the solution of the given system of equation.

Explanation:

First QUESTION:

Here the given set if equation are:

y = x + 15

y = 2 x

Substituting the value of y = 2 x in the first equation, we get:

y = x + 15 ⇒ 2 x = x + 15

or, 2 x - x = 15

⇒ x = 15

⇒ y = 2 x = 2 ( 15) = 30, or y = 30

Hence, x = 15, y = 30 is the SOLUTION of the given system of equation.

Second QUESTION:

Here the given set if equation are:

y = x +12

4 x + 2 y = 27​

Substituting the value of y = x + 12 in the second equation, we get:

4 x + 2 y = 27​ ⇒ 4 x + 2 (x + 12) = 27​

or, 4 x + 2(x) + 2 (12) = 27

⇒ 6 x = 27 - 24 = 3

⇒ x = 3 /6 = 0.5

Now, y = x + 12 = 0.5 + 12 = 12.5 or y = 12.5

Hence, x = 0.5 , y = 12.5 is the SOLUTION of the given system of equation.