Pre-Algebra Examples

$- 7 x^{2} - 6 x + 9 + - 3 x^{2} - x + 7$

Step 1

Replace all occurrences of $+$ $-$ with a single $-$ . A plus sign followed by a minus sign has the same mathematical meaning as a single minus sign because $1 \cdot - 1 = - 1$

$- 7 x^{2} - 6 x + 9 - 3 x^{2} - x + 7$

Step 2

Subtract $3 x^{2}$ from $- 7 x^{2}$ .

$- 10 x^{2} - 6 x + 9 - x + 7$

Step 3

Subtract $x$ from $- 6 x$ .

$- 10 x^{2} - 7 x + 9 + 7$

Step 4

Add $9$ and $7$ .

$- 10 x^{2} - 7 x + 16$