Question

Simplify
1) 4r+3-9r^2+7r

2) (4h^3+3h+1)-(-5h^3+6h-2)

3) 5k (3-4k)

4) (2x-3)(4x+3)

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

My answers:

1) 11r+3-9r^2

2) this one I am confused about

3) confused

4) 7x×7

5) 8x-6

Please help me

Answer 1

#2:
(4h^3+3h+1)-(-5h^3+6h-2)
think of it as
(4h^3+3h+1)-1(-5h^3+6h-2)
= 4h^3 + 3h + 1 + 5h^2 - 6h + 2
= 9h^2 -3h + 3

#3
5k (3-4k)
= 15k - 20k^2 by the distributive property

Answer 2

#4, oh dear!!!

(2x-3)(4x+3)
= 8x^2 + 6x - 12x - 9
= 8x^2 - 6x - 9

#5 , same as #4

(4x-3)(4x+3)
= 16x^2 + 12x - 12x - 9
= 16x^2 - 9 <--- called the difference of squares

make sure you are familiar with FOIL,
F : multiply the firsts
O : multiply the "outers"
I : multiply the "inners"
L: multiply the "lasts"

Answer 3

Uh ye