Factor this trinomial completely.

–12x2 + 45x + 12

a. –12x2 + 45x + 12
–3(4x2 + 15x – 4)
–3(4x – 1)(x + 4)
b. –12x2 + 45x + 12
–3(4x2 + 17x + 4)
–3(4x + 1)(x + 4)
c. –12x2 + 45x + 12
–3(4x2 – 15x – 4)
–3(2x + 1)(2x – 4)
d. –12x2 + 45x + 12
–3(4x2 – 15x – 4)
–3(4x + 1)(x – 4)

12x - 52

4x2 - 27x + 44

is correct.

16

x - 3

-  

4

x - 4

5 -  

x - 4

x - 3

·

(x - 3)(x - 4)

(x - 3)(x - 4)

=

16(x - 4) - 4(x - 3)

5(x - 3)(x - 4) - (x - 4)(x - 4)

=

16x - 64 - 4x + 12

5(x2 - 7x + 12) - (x2 - 8x + 16)

=

12x - 52

5x2 - 35x + 60 - x2 + 8x - 16

=

12x - 52

4x2 - 27x + 44

hello from mrbilldoesmath!

answer:

(7 x + 6 y) (49 x^2 - 42 x y + 36 y^2)

discussion:

the trick is to recognize that 343 = 7^3 and 216 = 6^3 and, in general,

a^3 + b^3 =   (a + b) (a^2 - a b + b^2).

in our case

343x^3+216y^3   =   (7x)^3 + (6y)^3

so take a = 7x and b = 6y in the above equation to get the answer.

you,

mrb

the equation is not included but the answer is (1.50, 2.00, 2.75)

step-by-step explanation: