Respuesta :

A) 2x to the power of 2 +13x-7
B) 3x to the power of 2 -11x -20
C) y to the power of 2 + 13y+36
D) b to the power of 2 -15b + 36

Answer:

A.) [tex]2x^2 + 13x - 7[/tex]

B.) [tex]3x^2 - 11x - 20[/tex]

C.) [tex]y^2 + 13y + 36[/tex]

D.) [tex]b^2 - 15b + 36[/tex]

Step-by-step explanation:

For all of these you want to multiply the first thingy (Ex. x) in the first parenthesis by the first in the second parenthesis (Ex. 2x) plus the first one in the first (Ex. x) times the second one in the second (Ex. -1) plus the second one in the first one (Ex. 7) times the first one in the second parenthesis (Ex. 2x)  plus the second one in the first parenthesis (Ex. 7) times the second one in the second (Ex. -1)

A.) (x + 7)(2x - 1) = (2x * x) + (-1 * x) + (7 * 2x) + (7 * -1) = 2x^2 -x + 14x - 7 = 2x^2 + 13x - 7

B.) (3x + 4)(x - 5) = (3x * x) + (3x * -5) + (4 * x) + (4 * -5) = 3x^2 - 15x + 4x - 20 = 3x^2 - 11x - 20

C.) (y + 9) (y + 4) = (y * y) + (4 * y) + (9 * y) + (9 * 4) = y^2 + 4y + 9y + 36 = y^2 + 13y + 36

D.) (b - 12)(b - 3) = (b * b) + (b * -3) + (-12 * b) + (-12 * -3) = b^2 - 3b - 12b + 36 = b^2 - 15b + 36