Question

Answer 1

1: \(=\left(x+8\right)\left(x-1\right)\)

2: \(=\left(x-7\right)\left(x+1\right)\)

3: \(=-\left(x-1\right)\left(x-4\right)\)

4: \(=-\left(x^2+8x-9\right)=-\left(x+9\right)\left(x-1\right)\)

5: \(=4x^2+7x-4x-7=\left(4x+7\right)\left(x-1\right)\)

6: \(=9x^2-9x+8x-8=\left(x-1\right)\left(9x+8\right)\)

Answer 2

1) \(x^2+7x-8=x^2-x+8x-8\)

 \(=\left(x^2-x\right)+\left(8x-8\right)=x\left(x-1\right)+8\left(x-1\right)\)

\(=\left(x+8\right).\left(x-1\right)\)

2) \(x^2-6x-7=x^2+x-7x-7\)

\(=\left(x^2+x\right)-\left(7x-7\right)=x\left(x+1\right)-7\left(x+1\right)\)

\(=\left(x-7\right).\left(x+1\right)\)

3) \(-x^2+5x-4=-x^2+x+4x-4\)

 \(=\left(-x^2+x\right)+\left(4x-4\right)=-x\left(x-1\right)+4\left(x-1\right)\)

\(=\left(-x+4\right).\left(x-1\right)\)

4) \(-x^2-8x+9=-x^2+x-9x+9\)

\(=\left(-x^2+x\right)-\left(9x+9\right)=-x\left(x-1\right)-9\left(x-1\right)\)

\(=\left(-x-9\right)\left(x-1\right)\)

5) \(4x^2+3x-7=4x^2-4x+7x-7\)

 \(=\left(4x^2-4x\right)+\left(7x-7\right)=4x\left(x-1\right)+7\left(x-1\right)\)

\(=\left(4x+7\right)\left(x-1\right)\)

6) \(9x^2-x-8=9x^2-9x+8x-8\)

 \(=\left(9x^2-9x\right)+\left(8x-8\right)=9x\left(x-1\right)+8\left(x-1\right)\)

\(=\left(9x+8\right)\left(x-1\right)\)

7) \(-16x^2+11x+5=-16x^2+16x-5x+5\)

\(=\left(-16x^2+16x\right)-\left(5x+5\right)=-16x\left(x-1\right)-5\left(x-1\right)\)

\(=\left(-16x-5\right)\left(x-1\right)\)

8) \(-4x^2-7x+11=-4x^2+4x-11x+11\)

\(=\left(-4x^2+4x\right)-\left(11x+11\right)=-4x\left(x-1\right)-11\left(x-1\right)\)

\(=\left(-4x-11\right)\left(x-1\right)\)

9) \(13x^2+7x-6=13x^2+13x-6x-6\)

\(=\left(13x^2+13\right)-\left(6x-6\right)=13x\left(x+1\right)-6\left(x+1\right)\)

\(=\left(13x-6\right)\left(x+1\right)\)