Question

Subtract $-{\mathrm{x}}^2+10\mathrm{x}-5$ from $5\mathrm{x}-10$.

Answer 1

Subtracting $-{\mathrm{x}}^2+10\mathrm{x}-5$ from $5\mathrm{x}-10$:

$$\begin{gathered} \left(5\mathrm{x}-10\right)-\left(-{\mathrm{x}}^2+10\mathrm{x}-5\right) \\ =5\mathrm{x}-10+{\mathrm{x}}^2-10\mathrm{x}+5 \\ ={\mathrm{x}}^2+5\mathrm{x}-10\mathrm{x}-10+5 \\ ={\mathrm{x}}^2-5\mathrm{x}-5 \end{gathered}$$

Therefore, the required answer is ${\mathrm{x}}^2-5\mathrm{x}-5$.