Question

Solve the system using substitution x+5y=0 3y+2x=-21

Answer 1

Ok done. Thank to me :>

Answer 2

`\left \{ {{x = -15} \atop {y=3}} \right.`

Explanation:

`\left \{ {{x + 5y = 0} (1) \atop {3y + 2x = -21}(2)} \right. <=> \left \{ {{x = -5y} \atop {3y + 2x = -21}} \right. <=> \left \{ {{x = -5y} \atop {3y + 2*(-5y) = -21}} \right. <=> \left \{ {{x = -5y} \atop {3y - 10y = -21}} \right. \\<=> \left \{ {{x = -5y } \atop {-7y = -21}} \right. <=> \left \{ {{x = -5y} \atop {y= 3 }} \right. <=> \left \{ {{x = -5 * 3} \atop {y=3}} \right.=> \left \{ {{x=-15} \atop {y=3}} \right.`