[products of binomials][section 37]

(1.) (y - 5)(y + 1) here is the problem

= y² + y - 5y - 5 foil multiply

= y² - 4y - 5 combine like terms

result: y² - 4y - 5

(2.) (p + 9)(p + 11) here is the problem

= p² + 11p + 9p + 99 foil multiply

= p² + 20p + 99 combine like terms

result: p² + 20p + 99

(3.) (m + n)(m - n) here is the problem

= m² - mn + mn - n² foil multiply

= m² - n² combine like terms

result: m² - n²

(4.) (m - n)(p - q) here is the problem

= mp - mq - np - nq foil multiply

result: mp - mq - np - nq

(5.) (3x - 2y)(3x + 2y) here is the problem

= 9x² + 6xy - 6xy - 4y² foil multiply

= 9x² - 4y² combine like terms

result: 9x² - 4y²

(6.) (m + 7)(m - 11) here is the problem

= m² - 11m + 7m - 77 foil multiply

= m² - 4m - 77 combine like terms

result: m² - 4m - 77

(7.) (y² + 3)(y² + 3) here is the problem

= y⁴ + 3y² + 3y² + 9 foil multiply

= y⁴ + 6y² + 9 combine like terms

result: y⁴ + 6y² + 9

(8.) (5x + 3)(x + 1) here is the problem

= 5x² + 5x + 3x + 3 foil multiply

= 5x² + 8x + 3 combine like terms

result: 5x² + 8x + 3

(9.) (10p + 3)(6p - 1) here is the problem

= 60p² - 10p + 18p - 3 foil multiply

= 60p² + 8p - 3 combine like terms

result: 60p² + 8p - 3

(10.) (2x + 5)(3x + 1) here is the problem

= 6x² + 2x + 15x + 5 foil multiply

= 6x² + 17x + 5 combine like terms

result: 6x² + 17x + 5