Question

Solve each of the following system of equations by substitution method.

$13x+11y=70,11x+13y=74$

• A. $(2,4)$
• B. $(3,4)$
• C. $(2,2)$
• D. None of these

Answer 1

Answer: (A)

$(2,4)$

Since, $13x+11y=70$...eq1 $11x+13y=74$......eq2

$x=\frac{70-11y}{13}$, put this value in eq2, we get

$11\left[\frac{70-11y}{13}\right]+13y=74$

$770-121y+169y=74\times 13$

$\Rightarrow y=4$

and
$x=\frac{70-11\left(4\right)}{13}$

$x=2$