Linear expressions

subtract. show work.

1. (9x++3)

2. ( -x+-5)

3. (3x++2)

4. (7x++2)

5. (9x-+4)

6. (9x--7)

i think the answer is a.( -3, -1 )

the absolute value function

x^2 + 81

we can factor this using difference of square binomials.

rewrite the equation:

x^2 - (-81)

factor:

(a^2 - b^2) = (√a^2 + √b^2)(√a^2 - √b^2)

(x^2 - (-81) = (x + √-81)(x - √-81)

we can remove the - from under the radical by multiplying it by i.

(x^2 - (-81) = (x + i√81)(x - i√81)

(x^2 - (-81) = (x + 9i)(x - 9i)

we can check our answer by using foil:

x^2 - 9ix + 9ix - 81i^2

x^2 - 81^2

i^2 = -1

x^2 + 81

they r 125, and 216

so the sequence goes 1,8,27,64,125,216