Question

What must be added to 1 – 2x + 3x2

to obtain 3 + 5x – 7x2?

Answer with proper working (no direct answer)

First and the correct answer will be marked as brainliest

Answer 1

3x2-2x+1
-7x2+5x+3
+. -. -
10x2-7x-2

Answer 2

Let 'a' be the number that must be added to 1 – 2x + 3x2 to obtain 3 + 5x – 7x2.
$1 - 2x + 3 {x}^{2} + a = 3 + 5x - 7 {x}^{2} \\ - 2x + 3 {x}^{2} + a = 3 - 1 + 5x - 7 {x}^{2} \\ - 2 x + 3 {x}^{2} + a = 2 + 5x - 7 {x}^{2} \\ a = 2 + 5x + 2x - 7 {x}^{2} - 3 {x}^{2} \\ a = 2 + 7x - 10 {x}^{2}$
Hope it helps uhh❤❤