Question

solve the following linear equation using cross multipication method.

3x - 4y = 2

y - 2x = 7​

Answer 1

I dont think so cross multiplication method is coming for boards coz it is deleted! Yet, here is your answer:

Step-by-step explanation:

3x − 4y = 2

y − 2x = 7

Solution: The above equation can be rewritten as:

3x − 4y = 2

−2x + y = 7

By method of cross multiplication,

$\frac{x}{b_1~ c_2~-~b_2~ c_1}$$=\frac{y}{c_1 ~a_2~-~c_2~ a_1}$$=\frac{1}{b_2 ~a_1~-~b_1~ a_2}$

Substituting the value in the above equation;

$\frac{x}{28~+~2}$$=\frac{y}{4~+~21}$$=\frac{1}{3~-~8}$

⇒ $\frac{x}{30}=\frac{y}{25}=\frac{-1}{5}$

⇒ x = −6 , y = −5