B.P.S.C. TRE-3 July, 2024

The values of $x$ and $y$ satisfying the equations $2x + 3y = 77$ and $3x + 2y = 73$ respectively are -

a12 and 18
b11 and 19
c13 and 17✓ Correct
dMore than one of the above
eNone of the above

Explanation

$$ \begin{aligned} 2x + 3y &= 77 \quad \dots(1) \\ 3x + 2y &= 73 \quad \dots(2) \end{aligned} $$ subtracting, equation (1) multiplying by 2 and equation (2) by multiplying 3 $$ 4x + 6y = 154 \quad \dots(3) $$ $$ -9x \pm 6y = -219 \quad \dots(2) $$ $$ -5x = -65 \\ x = 13 $$ Substituting the value of $x$ in equation (1) - $$ 2 \times 13 + 3y = 77 $$ $$ 26 + 3y = 77 $$ $$ 3y = 77 - 26 $$

general-mental-ability