harder factorisation

Resolve into factors:

15 y² + 22y – 48

Answer:

Multiply and divide the expression by 15.

So,  ¹/₁₅ {(15y)² + 22.15y – 48.15}

Let 15y = x

Therefore, 1/15 {x² + 22x - 720}

=¹/₁₅{x² + 40x – 18x - 720}

=¹/₁₅(x+40)(x-18)

=¹/₁₅(15y +40)(15y- 18)  substituting x = 15y

= (3y +8)(5y -6)

Resolve into factors:

28 + 31p -5p²

Answer:

28 + 31p -5p²

=28 + 35p – 4p - 5p²

=7(4 + 5p) –p(4 + 5p)

= (7 – p)(4 + 5p)

 

Resolve into factors:

15 + 16p – 15p²

Answer:

15 + 16p – 15p²

Multiply and divide the numerator and denominator by 15

= ¹/₁₅{15.15 + 15.16p – (15p)²}

Let, 15p = y

= -¹/₁₅{y2 – 16y +15} 

=-¹/₁₅{y2 – 15y - y +15} 

=-¹/₁₅{y(y – 15) -1( y -15)} 

= -¹/₁₅(y -1)(y – 15)

= -¹/₁₅(15p -1)(15p -15)

= - (15p -1)(p – 1)

= (15p -1)(1- p)