When x^4+6x^3-ax^2-45x-15 is divided by x^2-x-6 the remainder is 3. What is a?
We can write \(x^4+6x^3-ax^2-45x-15=q(x)(x^2-x-6)+3\). Factoring \(x^2-x-6\) gives \((x-3)(x+2)\). So what significant numbers can you plug into the first equation to get the answer? Can you take it from here?
Yes thank you for your help!