Solve the system of equations by the addition method.

Mathematics

2 answers:

Eva8 [605]2 years ago

8 0

$\left \{ {{\frac{x}{2}-y=7 } \atop {-\frac{x}{7}+\frac{2y}{7}= -2 }} \right. \left \{ {{\frac{x}{2}.2-2y=2.7} \atop {-\frac{x}{7}.7+\frac{2y}{7}.7= -2.7}} \right. \left \{ {{x-2y=14} \atop {-x+2y=-14}} \right. \left \{ {{0x=0} \atop {y={\frac{x}{2}-7}} \right.$

ANSWER: B

ok done. Thank to me :>

larisa [96]2 years ago

7 0

Integer solution

x= 2n, y=n-7, nEZ

real solution or you can use inverse operation to have addition

y= x/2-7 y=x[multiplied by] 2+7

oh and for the first one the choice is A the second one im sorry im not sure

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