**Answer:**

(a) (x+3) (x+9)

(b) (x+4) (x-4)

(c) (x-4i) (x+4i)

(d) (-2+i) (-2-i)

**Step-by-step explanation:**

We have given the quadratic expressions and we have to write these expressions in factor form

(a)

It can be written as

Now taking (x+9) as common

(b)

We know the algebraic equation

(c)

(d)

It can be written as

**Answer:**

First lets open parenthesis using the distributive property. So we multiply everything in the parenthesis by 2. 5x*2 = 10x. 4*2 = 8. So we have 10x + 8 = 8. We subtract 8 from both sides and we get 10x = 0. So we divide both sides by 10 and 0/10 = 0. x=0. So the answer to x is

<h2><u>

**0**</u></h2>

I am pretty sure the answer is 2,520.

**Answer:**

m = 3/17

**Step-by-step explanation:**

M = -1y/-11c + 16y/-8x = 3/17

**Answer:**

A: 114, B: 84

**Step-by-step explanation:**

Let A be weight of Train A, B be weight of Train B. Since A is heavier than B by 30 tons, A = B + 30. Since A + B = 198, you can substitute for A to get (B+30) + B = 198. Then simplify so 2B = 168 and B = 84.

Then plug B into A = B+30 to get A = 114.