Question

4.

Answer 1

Answer:

$(10, 0)$

Step-by-step explanation:

Let's try all the options:

$\left \{ {{2x + y = 20} \atop {4x-2y = 40} \right.$

Considering $(10, 0)$:

$\left \{ {{2(10) + 0 = 20} \atop {4(10)-2(0) = 40} \right.$

$\left \{ {{20 + 0 = 20} \atop {40-0 = 40} \right.$

$\left \{ {{20= 20} \atop {40 = 40} \right.$

Considering $(0, 10)$:

$\left \{ {{2(0) + 10 = 20} \atop {4(0)-2(10) = 40} \right.$

$\left \{ {{0 + 10 = 20} \atop {0-20 = 40} \right.$

$\left \{ {{10= 20} \atop {-20 = 40} \right.$

$\left \{ {{10\neq 20} \atop {-20 \neq 40} \right.$

Considering $(4, 2)$:

$\left \{ {{2(4) + 2 = 20} \atop {4(4)-2(2) = 40} \right.$

$\left \{ {{8 + 2 = 20} \atop {8-4 = 40} \right.$

$\left \{ {{10= 20} \atop {4 = 40} \right.$

$\left \{ {{10\neq 20} \atop {4 \neq 40} \right.$

Considering $(10, -10)$:

$\left \{ {{2(10) -10 = 20} \atop {4(10)-2(-10) = 40} \right.$

$\left \{ {{20 -10 = 20} \atop {40+20 = 40} \right.$

$\left \{ {{10= 20} \atop {60 = 40} \right.$

$\left \{ {{10\neq 20} \atop {60 \neq 40} \right.$