Answer:
Answer: a = - 12
Step-by-step explanation:
We have here two equations, one 18x + 12y = 36, the other ax - 8y = - 24;
Now if we were to consider making these two equations have a common y co - efficient, we would multiply the top equation by 2, the bottom consecutively by - 3. This would make a standard 24y ;
2 * ( 18x + 12y = 36 ), ⇒ 36x + 24y = 72
+ - 3 * ( ax - 8y = - 24 ) + - 3ax + 24y = 72
As you can see, all terms are equivalent, besides that of the co - efficient of x. Knowing that, it would be ax must be multiplied by - 3 to receive 36x, as the bottom equation is multiplied by - 3, where all terms are equivalent to the top terms;
- 3 * ax ⇒ 36x, - 3 * - 12x = 36x,
Answer: a = - 12
