Question

Find the value of $x$ given that $4x+2y=24$ and $\frac{7y}{2x}=7$.

• A. $3$
• B. $1$
• C. $4$
• D. $6$

Answer 1

The correct option is A $3$

Let $4x+2y=24...\left(1\right)$

$\frac{7y}{2x}=7$

$\Rightarrow 7y=14x$

$\Rightarrow -14x+7y=0...\left(2\right)$

Multiply $\left(1\right)$ by $7$ and $\left(2\right)$ by $2$, we get

$\Rightarrow 28x+14y=168...\left(3\right)$

$\Rightarrow -28x+14y=0...\left(4\right)$

Subtract $\left(4\right)$ from $\left(3\right)$, we get

$\Rightarrow 56x=168$

$\Rightarrow x=\frac{168}{56}=3$