Question

2x-y=0;x+y=135
answer the question by substitution method. ​

Answer 1

Answer:

$x = 45,y = -90$

Step-by-step explanation:

Given equations:  $2x + y= 0$        --$(1)$

                              $x+y = 135$      --$(2)$

We have to solve this using substitution method.

In substitution method we have to substitute the value of a variable from one equation into the other, hence, finding its solution

⇒ $2x + y = 0$

⇒ $y = -2x$

Substituting this value of $y$ in equation $(2)$

⇒ $x + (2x) = 135$

⇒ $3x = 135$

⇒ $x = \frac{135}{3}$

⇒ $x = 45$

Now substituting this value of $x$ in equation $(1)$

⇒ $2(45) + y = 0$

⇒ $90 + y = 0$

⇒ $y = -90$

∴ The solution of $2x + y = 0, x+y=135$ is $(45,-90)$