118,254 views
35 votes
35 votes
1. 12x^2-8x

2. x^2+5x-36

3. 3x^2+10x+8

Please show all the work for how to solve these problems, thanks.​

User Munsifali
by
3.2k points

2 Answers

8 votes
8 votes

Answer:

Explanation:

1) the two members of the expression has 4x in common, so we can rewrite it as: 4x(3x-2)

2) we have to find two numbers that multipied give -36 and that added up give 5

the two number are 9 and -4

we can rewrite the expression as : (x+9)(x-4)

3) we have to solve the associated equation

3x^2+10x+8 = 0

Δ/4 = 25-24 = 1

x1 = (-5+1)/3 = -4/3

x2 = (-5-1)/3 = -2

now we can rewrite the expression as

3(x+4/3)(x+2) = (3x+4)(x+2)

User Rashawna
by
3.1k points
18 votes
18 votes

Answer:

1. 12x^2-8x

taking common 4x

4x(x-2)

2. x^2+5x-36

doing middle term factorization

x²+9x-4x-36

x(x+9)-4(x+9)

(x+9)(x-4)

3. 3x^2+10x+8

Doing middle term factorization

3x²+6x+4x+8

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

(x+2)(3x+4)

User Prakash Palnati
by
2.8k points